2020

• Statement 1 is incorrect. The Supreme Court struck down Regulation 27 of the Aadhaar Authentication Regulations, which had permitted retention of authentication records for five years, and capped retention at six months, not three months.
• Statement 2 is correct. Section 57 of the Aadhaar Act, which allowed body corporates and individuals to demand Aadhaar authentication under any contract, was struck down, so the State cannot contract with private corporations for sharing Aadhaar data.
• Statement 3 is incorrect. The same reasoning bars private service providers, including insurers, from making Aadhaar mandatory.
• Statement 4 is correct. Section 7 was expressly upheld, so Aadhaar may be insisted upon for subsidies, benefits and services financed from the Consolidated Fund of India. Only 2 and 4 stand, giving (b).
• Option (a) fails on the three month figure in statement 1, (c) fails because insurance is a private service, and (d) carries both the incorrect statements.

A constitutional amendment under Article 368 must be passed separately by each House by the prescribed special majority, and there is no provision for a joint sitting to break a deadlock. The two Houses are therefore exactly equal here, which makes (b) correct.

• Option (a) is wrong because Article 312 gives the Rajya Sabha a power the Lok Sabha does not have at all, namely the exclusive power to pass the enabling resolution for a new All India Service, so the power is greater, not equal.
• Option (c) is wrong because a no confidence motion lies only in the Lok Sabha, the council of ministers being collectively responsible to the popular House alone under Article 75(3).
• Option (d) is wrong because cut motions attach to the demands for grants, which are voted only by the Lok Sabha under Article 113(2).

• Statement 1 is correct. The MPLADS guidelines confine the scheme to works creating durable community assets, with health, education, drinking water and sanitation as priority sectors.
• Statement 2 is correct. Fifteen per cent of the annual entitlement is earmarked for areas with Scheduled Caste population and seven and a half per cent for areas with Scheduled Tribe population.
• Statement 3 is incorrect and is the key to the question. MPLADS funds are expressly non lapsable, so unspent amounts are carried forward and the entitlement accumulates.
• Statement 4 is correct. The district authority is required to inspect at least ten per cent of the works under implementation each year. Correct combination is 1, 2 and 4, giving (d).
• Options (a) and (b) drop correct statements, and (c) admits the non lapsability error.

Article 17 abolishes untouchability and forbids its practice in any form. It sits within Articles 14 to 18, which together constitute the Right to Equality, so (d) is correct.

• Option (a) is wrong because the Right against Exploitation covers Articles 23 and 24, dealing with traffic in human beings, forced labour and child labour in hazardous employment.
• Option (b) is wrong because the Right to Freedom covers Articles 19 to 22, dealing with the six freedoms, protection in respect of conviction, life and personal liberty and preventive detention.
• Option (c) is wrong because the Right to Constitutional Remedies is Article 32, the enforcement mechanism rather than a substantive protection against discrimination.

Article 50, a Directive Principle, directs the State to take steps to separate the judiciary from the executive in the public services of the State. Hence (b).

• Option (a) is wrong because the Preamble declares objectives such as justice, liberty, equality and fraternity but says nothing about the separation of the two branches.
• Option (c) is wrong because the Seventh Schedule distributes legislative subjects between the Union and the States and is a federal instrument, not a separation of powers instrument.
• Option (d) is wrong because the mandate is textual, not conventional, even though its implementation was carried out progressively through the Criminal Procedure Code of 1973.

Section 3 of the Fiscal Responsibility and Budget Management Act, 2003 requires the Central Government to lay before both Houses, along with the annual financial statement, a Medium Term Fiscal Policy Statement, a Fiscal Policy Strategy Statement and a Macro Economic Framework Statement. The mandate is therefore statutory, giving (d).

• Option (a) is wrong because the requirement is written law, not convention.
• Option (b) is wrong because Article 112 mandates only the annual financial statement and Article 110(1) merely defines a money bill.
• Option (c) is wrong because Article 113 governs the procedure for demands for grants and their voting by the Lok Sabha, not accompanying fiscal documents.

Constitutionalism means government restrained by law, with defined powers, enforceable rights and institutional checks. The defining feature is limitation, so (d) is correct.

• Option (a) is wrong because legislative supremacy is a distinct idea and a legislature with unlimited power is precisely what constitutionalism restrains.
• Option (b) is wrong because popular support is the mark of democracy, and an elected government that respects no limits is a majoritarian rather than a constitutional government.
• Option (c) is wrong because the number of parties is a feature of the party system and has no necessary connection with constitutional limitation, as single party and two party systems can both be constitutional.

Section 12 of the Legal Services Authorities Act, 1987 lists the entitled categories, which include members of Scheduled Castes and Scheduled Tribes, victims of trafficking, women and children, persons with disability, victims of mass disaster and violence, industrial workmen, persons in custody, and persons whose annual income falls below the ceiling prescribed by the appropriate government.

• Statement 4 is clearly incorrect, since senior citizens are not entitled as a class merely by age and must satisfy a means or category test, and this eliminates (b) and (d).
• Statement 3 is incorrect because Other Backward Classes are not a listed category and no OBC specific income ceiling exists in the Act, which eliminates (c). By elimination the answer is (a), which rests on a general low income ceiling and on transgender persons being covered following the NALSA judgment of 2014 and subsequent legal services schemes.

• Pair 1 is correct. The Alma-Ata Declaration of 1978 is the foundational statement on primary health care and the goal of health for all.
• Pair 2 is incorrect. The Hague Conventions of 1899 and 1907 codify the laws and customs of war and set up the Permanent Court of Arbitration; biological and chemical weapons are governed by the Geneva Protocol of 1925, the Biological Weapons Convention of 1972 and the Chemical Weapons Convention of 1993.
• Pair 3 is correct. The Talanoa Dialogue is the facilitative stocktake process under the Paris Agreement, using the Fijian tradition of inclusive storytelling.
• Pair 4 is incorrect. The Under2 Coalition is a memorandum of understanding among states and regions committing to deep decarbonisation, and has nothing to do with child rights. Correct pairs are 1 and 3, giving (c).
• Options (a) and (d) admit the Hague error, and (b) rests entirely on the Under2 error.

The defining feature of the parliamentary system is that the executive is drawn from and continuously answerable to the legislature and survives only while it retains its confidence. Hence (b).

• Option (a) describes a national or grand coalition, an occasional arrangement and not a defining feature.
• Option (c) describes direct popular mandate and recall, which is closer to the presidential model where the executive is separately elected and cannot be removed by the legislature on political grounds.
• Option (d) describes a fixed term executive, which again is the presidential model or a system with constructive votes and anti defection style rigidity, and it contradicts the very idea of collective responsibility.

Article 38 directs the State to secure a social order for the promotion of the welfare of the people, and Articles 39 to 47 spell out the substantive content of that welfare obligation. The Directive Principles are therefore the declaration of the welfare state ideal, giving (a).

• Option (b) is wrong because Fundamental Rights are essentially negative restraints on state power, protecting the individual against the State rather than obliging it to provide.
• Option (c) is wrong because the Preamble declares socialism and justice as objectives but does not spell out a welfare programme, and the question asks for the part that declares the ideal in operative terms.
• Option (d) is wrong because the Seventh Schedule is a distribution of legislative competence.

• Statement 1 is clearly incorrect. The Constitution nowhere uses or defines the expression basic structure. The doctrine was evolved judicially in Kesavananda Bharati in 1973 and its contents have been added to case by case, deliberately without an exhaustive list.
• Statement 2 is treated as incorrect by the official key on the reasoning that the Constitution nowhere uses the phrase judicial review and nowhere states the purpose attributed to it in the statement; the power is inferred from Articles 13, 32, 131 to 136, 226 and 227. On that reading neither statement stands, giving (d).
• Options (a) and (c) fail on the basic structure error, and (b) fails only if one accepts the strict textual reading of statement 2.

Marx envisaged the withering away of the state once class antagonism ended, and Gandhi envisaged enlightened anarchy, a Ramarajya of self governing village republics in which the coercive state becomes unnecessary. The routes differ entirely but the terminal vision converges, giving (a).

• Option (b) is wrong because Gandhi rejected class conflict and proposed trusteeship, in which capital and labour are reconciled through moral transformation rather than confrontation.
• Option (c) is wrong for the same reason, since trusteeship retains private ownership while redefining the owner as a steward for society.
• Option (d) is wrong because Gandhi treated moral and spiritual factors as primary and explicitly rejected the primacy of the economic base in shaping consciousness.

Kesavananda Bharati settled that the Preamble is a part of the Constitution, overruling Berubari Union, and it is amendable, as the Forty second Amendment demonstrated. At the same time the Preamble is not a source of enforceable rights and confers no power on any organ; it is used to resolve ambiguity in other provisions. It therefore has legal significance but no independent operative effect, giving (d).

• Option (a) is wrong in denying any legal effect at all, since courts routinely use the Preamble as an aid to interpretation.
• Option (b) is wrong on the Berubari position that Kesavananda displaced.
• Option (c) is wrong because unlike other parts the Preamble is not enforceable in itself and no petition lies on the Preamble alone.

A member's quota with the International Monetary Fund is subscribed partly in reserve assets, historically gold and now Special Drawing Rights or widely accepted currencies, and partly in its own currency. The reserve asset portion, about a quarter of quota, is the reserve tranche, formerly the gold tranche, and a member may draw on it automatically and unconditionally. This makes (d) correct.

• Option (a) is wrong because World Bank lending is project and policy based through IBRD and IDA and has no tranche linked to quota subscription.
• Option (b) is wrong because the term is not part of central bank operations, which concern open market operations, policy rates and reserve requirements.
• Option (c) is wrong because the World Trade Organization is a rule making and dispute settlement body and extends no credit at all.

Article 37 states in terms that the provisions of Part IV shall not be enforceable by any court, but that the principles are nevertheless fundamental in the governance of the country and it shall be the duty of the State to apply them in making laws.

• Statement 1 is therefore incorrect and statement 2 correct, and statement 3 is correct as a direct restatement of the second half of Article 37. The answer is 2 and 3, giving (d).
• Options (a) and (c) fail because they assert enforceability, which is the exact opposite of the constitutional text, and (b) is incomplete because it drops the positive obligation on the State that Article 37 also creates.

• Statement 2 is clearly incorrect. Section 8 of the Representation of the People Act, 1951 disqualifies a convicted person for the period of imprisonment and for a further six years from release, not permanently. That alone eliminates (b) and (c).
• Statement 1 is treated as incorrect because mere eligibility to vote is not the test. Article 164(4) permits a non member to hold office as minister for six months, but the person must possess the qualifications for membership of the State legislature, which include a higher minimum age of twenty five for the Legislative Assembly and thirty for the Legislative Council, whereas voting eligibility begins at eighteen. Neither statement stands, giving (d).
• Option (a) fails on this age and qualification distinction.

• Statement 1 is correct. Article 85(1) empowers the President to summon each House at such time and place as he thinks fit, and sessions have occasionally been held outside the usual seat.
• Statement 2 is incorrect and is the discriminating statement. The Constitution nowhere provides for three sessions. It stipulates only that six months shall not intervene between the last sitting in one session and the first sitting in the next; the Budget, Monsoon and Winter sessions are a matter of convention.
• Statement 3 is correct, since no minimum number of sitting days is prescribed anywhere, a recurring subject of reform proposals. Correct combination is 1 and 3, giving (c).
• Options (b) and (d) admit the three sessions error, and (a) drops a correct statement.

• Pair 1 is incorrect. Aurang is a Persian term for a warehouse or manufactory, the depot where goods were collected from weavers and artisans before export by the Company. It has no connection with the treasury.
• Pair 2 is correct. The banian was the Indian intermediary, financier and agent who supplied capital, local knowledge and access to markets for Company servants and their private trade.
• Pair 3 is correct. Mirasidars were hereditary landholders, chiefly in the Tamil country, who held mirasi rights and were recognised as the parties liable to pay revenue to the State. Correct pairs are 2 and 3, giving (b).
• Options (a) and (d) admit the aurang error and (c) drops the banian pair.

• Statement 1 is incorrect. The Sthaviravadins, the elders, are the conservative school that survives as Theravada and is grouped under Hinayana. They stood in opposition to the Mahasanghikas, from whose line Mahayana tendencies emerged.
• Statement 2 is correct. The Lokottaravadins, who held that the Buddha was transcendent and that his earthly life was an appearance, were an offshoot of the Mahasanghika school.
• Statement 3 is correct. The Mahasanghika elevation of the Buddha from teacher to object of devotion, together with the bodhisattva ideal, supplied the theological foundation on which Mahayana developed. Correct combination is 2 and 3, giving (b).
• Options (a) and (d) misplace the Sthaviravadins in Mahayana, and (c) drops the Lokottaravadin link.

The decisive constraint is the time frame, the first half of the nineteenth century. Cheap machine made Lancashire cloth, admitted at low duties after the ending of the Company monopoly in 1813, destroyed the market for Indian handloom products and produced the deindustrialisation described by contemporaries and by later nationalist economists, so (a) is correct.

• Option (b) is wrong because mechanised mills in India began only with the Bombay cotton mill of 1854 and the Calcutta jute mill of 1855, both in the second half of the century.
• Option (c) is wrong because the first railway line ran from Bombay to Thane in 1853 and network expansion followed later.
• Option (d) is wrong because the policy ran the other way, with light duties on British imports and heavy duties on Indian goods entering Britain.

Mahendravarman I ruled from about 600 to 630 and marks the consolidation of Pallava power at Kanchi, so event 2 is earliest. Gopala was elected founder of the Pala dynasty in Bengal in about 750, so event 4 follows. Mihira Bhoja, the greatest of the Gurjara Pratiharas, ruled from about 836 to 885, so event 1 comes next. Parantaka I ruled from 907 to 955 and carried the imperial Chola expansion begun by Vijayalaya to a new level, so event 3 is last. The sequence is 2, 4, 1, 3, giving (c).

• Options (b) and (d) place the Cholas first, which is impossible since Parantaka is a tenth century ruler.
• Option (a) places the Pratiharas before the Palas, reversing an interval of nearly a century.

The hundi was an indigenous credit instrument, an unconditional written order to pay a sum to a named party, which allowed merchants to transfer value across long distances without carrying coin and to obtain short term credit. Its appearance in post Harsha sources is evidence that commercial activity and merchant banking networks persisted despite the general contraction of long distance trade in the period. Hence (c).

• Options (a) and (d) describe administrative or feudal communications, which have no connection with the term.
• Option (b) describes an account book, which in the Indian mercantile tradition would be a bahi khata and is a record rather than a negotiable instrument. The key distinction the question tests is negotiability, since the hundi could be endorsed and transferred.

Desher Katha, published in Bengali in 1904, was an exposition of the economic drain and of the psychological hold colonial rule exercised over the educated Indian mind.

• Statement 1 is correct, since Deuskar's central argument was that the most dangerous conquest was the conquest of the mind, which he described in terms of a hypnotic spell.
• Statement 2 is correct, since the book sold in tens of thousands during the Swadeshi years and its themes fed directly into jatra, street performance and swadeshi folk song before it was proscribed in 1910.
• Statement 3 is incorrect and is the discriminating statement. Deuskar, a Marathi speaking writer settled in Bengal, used desh to mean India as a whole, and the pan Indian sense of the word was precisely what gave the book its nationalist force. The answer is 1 and 2, giving (a).
• Options (b), (c) and (d) all admit the Bengal specific reading of desh.

On the substance, statement 1 is correct, since the Congress agreed to attend the Second Round Table Conference.

• Statement 2 is correct as printed in English, the ordinances issued to suppress the Civil Disobedience Movement being withdrawn.
• Statement 3 is incorrect, and is the well known trap; Gandhi pressed for a public enquiry into police excesses and Irwin refused, Gandhi accepting the refusal in the interest of a settlement.
• Statement 4 is correct, since the amnesty extended only to prisoners not convicted of or charged with violence. The intended answer would therefore be 1, 2 and 4, that is (b). The item was nevertheless dropped by the Commission, one of two dropped items in this paper.

Gopal Baba Walangkar, a retired army man from the Mahar community and an associate of Jyotiba Phule, began Vital Vidhvansak in 1888. It is recognised as the first periodical addressed specifically to the untouchable communities and it attacked the scriptural basis of caste, giving (a).

• Option (b) is wrong because Phule founded the Satyashodhak Samaj in 1873 and wrote Gulamgiri, but the journal in question was Walangkar's; Phule's associated periodical was Deenbandhu, brought out by Krishnarao Bhalekar.
• Option (c) is wrong because Gandhi's Harijan began only in 1933 and was addressed to a caste Hindu readership as much as to Dalits.
• Option (d) is wrong because Ambedkar's Mooknayak dates from 1920 and Bahishkrit Bharat from 1927, both well after 1888.

Both terms are units of land measurement recorded in Gupta period copper plate grants from Bengal, including the Damodarpur plates. They are sowing capacity measures, the area sown by one kulya or one drona of seed respectively, which is why the vapa suffix, meaning sowing, attaches to each. Hence (a).

• Option (b) is wrong because the coin denominations of the period are dinara, rupaka and karshapana.
• Option (c) is wrong on two counts, since these are agrarian measures applied to cultivated rural land, not a classification of urban plots; vastu terms cover the latter.
• Option (d) is wrong because the terms carry no ritual meaning. The wider significance is that seed capacity measurement, rather than area measurement, indicates the agrarian and localised character of the early medieval land grant economy.

The passage is a close rendering of Ashoka's Major Rock Edict XII, which enjoins restraint of speech, concourse between sects and honour to other sects as the path of dhamma. Hence (a).

• Option (b) is wrong because Samudragupta's principal epigraph, the Allahabad pillar prashasti composed by Harishena, is a catalogue of conquests and royal accomplishments and carries no ethical exhortation to subjects.
• Option (c) is wrong because Harshavardhana is known chiefly through Banabhatta's Harshacharita and the account of Xuanzang rather than through moral edicts addressed to the population.
• Option (d) is wrong because Krishnadeva Raya's Amuktamalyada is a Telugu poem containing counsel on statecraft directed at a ruler, not an inscription instructing subjects on sectarian tolerance.

In Mahayana doctrine the paramitas are the perfections cultivated by one who takes the bodhisattva vow, classically six in number, namely giving, moral conduct, patience, energy, meditation and wisdom. Hence (c).

• Option (a) is wrong because the earliest aphoristic legal texts are the Dharmasutras of Gautama, Baudhayana, Apastamba and Vasishtha.
• Option (b) is wrong because schools rejecting Vedic authority are the nastika systems, Charvaka, Buddhism and Jainism.
• Option (d) is wrong because the great southern trading corporations are the Ayyavole or Five Hundred Svamis of Aihole, the Manigramam and the Nanadesi. The trap here is that all four options describe genuine categories from Indian cultural history, so elimination alone will not work and the term itself must be known.

Rakhmabai was married in childhood to Dadaji Bhikaji and on attaining adulthood refused to live with him. He sued for restitution of conjugal rights, so statement 3 is correct and the litigation is the leading Indian case on that remedy. The proceedings turned on whether a marriage contracted in infancy could bind an adult woman, which brought the question of the age at which consent becomes meaningful into public debate and contributed directly to the Age of Consent Act of 1891, so statement 2 is correct.

• Statement 1 is incorrect. Rakhmabai went on to study medicine in England and became one of India's first practising women doctors, but the case itself raised no issue of a right to education. The answer is 2 and 3, giving (b).
• Options (a), (c) and (d) all import the education claim.

The decisive cause was the synthesis of artificial indigo, achieved by Adolf von Baeyer and commercialised by BASF from 1897, which collapsed the world price of the natural dye and destroyed the profitability of Indian plantations. Hence (b).

• Option (a) is wrong on timing and effect, since the Blue Rebellion of 1859 to 1860 in Bengal ended the system in the lower Gangetic districts a full generation earlier but did not cause the general decline; peasant resistance was a consequence of the crisis in Bihar rather than its cause.
• Option (c) is wrong because national leaders took the question up only after the industry was already dying, Gandhi's Champaran intervention coming in 1917.
• Option (d) is wrong because government regulation was slight and generally sympathetic to planters. The key word in the stem is inventions, which points squarely at synthetic dye.

Fort William College was founded in 1800 to train newly arrived Company writers in Indian languages, law, custom and revenue practice before they took up district posts, Wellesley's stated concern being the ignorance and youth of civil servants sent out from England. Hence (d).

• Option (a) is wrong because the Court of Directors in fact disapproved of the institution as expensive and ordered its curtailment, which is why Haileybury was set up in England in 1806 to do the preliminary training there.
• Option (b) is wrong because the revival of oriental learning was the purpose of the Asiatic Society founded by William Jones in 1784 and of the Calcutta Madrasa and Benares Sanskrit College.
• Option (c) is wrong because William Carey's appointment to teach Bengali and Sanskrit was a consequence of the College, not a motive for founding it.

Ulgulan, meaning the great tumult, is the Mundari name for the movement led by Birsa Munda in the Chhotanagpur region between 1899 and 1900, directed against dikus, moneylenders and missionaries and against the erosion of the khuntkatti communal tenure. Hence (d).

• Option (a) is wrong because the Revolt of 1857 is described in the sources as the sepoy mutiny, the first war of independence or simply the great rebellion, never as ulgulan.
• Option (b) is wrong because the Mappila rising in Malabar was an agrarian and communal tenant revolt in the Ernad and Valluvanad taluks.
• Option (c) is wrong because the Indigo revolt is known as the Nil Bidroha or Blue Rebellion. The outcome of the ulgulan was the Chhotanagpur Tenancy Act of 1908, which recognised khuntkatti rights.

• Statement 1 is incorrect. Panini, author of the Ashtadhyayi, belongs to about the fifth or fourth century before the common era, several centuries before the Shungas. The grammarian associated with Pushyamitra Shunga is Patanjali, author of the Mahabhashya, who is traditionally said to have officiated at his ashvamedha.
• Statement 2 is incorrect. Amarasimha, author of the Amarakosha, is counted among the navaratna at the court of Chandragupta II, not of Harshavardhana. Harsha's court is associated with Banabhatta and Mayura.
• Statement 3 is correct, Kalidasa being the best known of the same nine gems. Only statement 3 stands, giving (c).
• Options (a) and (d) carry the Panini error and (a), (b) and (d) carry the Amarasimha error, so recognising either misattribution isolates the answer.

Pronuclear transfer is one of the two principal mitochondrial replacement techniques. Both the mother's egg and a donor egg are fertilised, the two pronuclei are removed from the mother's zygote and transferred into the enucleated donor zygote, which retains healthy donor mitochondria. The child inherits nuclear DNA from both parents and mitochondrial DNA from the donor, so maternally transmitted mitochondrial disease is avoided. Hence (d).

• Option (a) is wrong because in vitro fertilisation of an egg by sperm is ordinary IVF or, where a single sperm is injected, intracytoplasmic sperm injection.
• Option (b) is wrong because that describes germline gene therapy directed at spermatogonial cells, an entirely separate line of work.
• Option (c) is wrong because deriving embryos or embryo like structures from stem cells is the field of synthetic embryology, unrelated to pronuclear manipulation.

• Statement 1 is correct, since reinforcement learning applied to cooling and process control has demonstrably cut industrial and data centre energy use.
• Statement 3 is correct, since image classification models are in clinical use for diabetic retinopathy, tuberculosis screening and histopathology.
• Statement 4 is correct, since neural text to speech is mature and deployed.
• Statement 5 is clearly incorrect, since wireless power transfer is a problem of electromagnetic induction and resonance in physics and hardware, and no software technique can accomplish it.
• Statement 2 is treated as incorrect by the official key, on the view that machine generated stories and songs then lacked genuine meaning. The answer as keyed is 1, 3 and 4, giving (b).
• Options (a), (c) and (d) all admit the wireless power error.

• Statement 1 is correct, since roughly 380 to 780 nanometres is the visible band and VLC modulates light emitting diodes within it.
• Statement 2 is incorrect and is the discriminating statement. VLC is inherently short range and requires line of sight, since visible light neither penetrates walls nor travels far without collimation; long range optical wireless is free space optical communication, a distinct technology.
• Statement 3 is correct, since demonstrated VLC data rates run into gigabits per second against a few megabits per second for classic Bluetooth.
• Statement 4 is correct in the practical sense, since VLC does not interfere with radio frequency equipment, which is why it is attractive in aircraft cabins, operating theatres and other electromagnetically sensitive spaces. The answer is 1, 3 and 4, giving (c).

• Statement 1 is correct as a description of a public permissionless chain, which is a distributed append only ledger replicated across nodes, open to inspection and controlled by no single participant, with consensus rather than an administrator determining validity.
• Statement 2 is incorrect and is the obvious eliminator. Cryptocurrency was the first application, not the structure; the same ledger carries land records, supply chain provenance, digital certificates and smart contracts.
• Statement 3 is correct, since a permissionless chain requires no gatekeeper's approval to build upon, which is the precise sense in which the technology is called permissionless. The answer is 1 and 3, giving (d).
• Options (b) and (c) rest on the cryptocurrency only error, and (a) drops the permissionless character, which is one of the defining features.

• Statement 1 is correct, since functionalised nanotubes are established vehicles for drug and antigen delivery, the high surface area and ability to cross membranes being the attraction.
• Statement 3 is correct, since their electrical conductivity changes on binding of a target molecule, which is the basis of nanotube field effect biosensors.
• Statement 4 is accepted as correct by the key on the strength of work showing enzymatic degradation of carboxylated nanotubes by peroxidases, including myeloperoxidase released by neutrophils.
• Statement 2 is treated as incorrect by the key. The keyed answer is therefore 1, 3 and 4, giving (c), with (a) and (d) rejected for including statement 2 and (b) rejected for dropping statement 1.

The description matches a space based gravitational wave observatory, in which laser interferometry between free falling test masses measures the minute changes in separation produced by a passing wave. Only the Evolved LISA concept involves three spacecraft in an equilateral formation with arms of order a million kilometres, so (d) is correct.

• Option (c) is the intended trap and is wrong because LISA Pathfinder, launched in 2015, was a single spacecraft carrying two test masses a few tens of centimetres apart, a technology demonstrator for drag free control rather than an interferometer between craft.
• Option (a) is wrong because Voyager 2 is a single outer planet flyby probe now in interstellar space.
• Option (b) is wrong because New Horizons is a single spacecraft that flew past Pluto in 2015 and the Kuiper belt object Arrokoth in 2019.

• Statement 1 is correct, since germline editing of gametes and of the gamete producing cells is technically achievable, whatever the ethical and regulatory bar on its use.
• Statement 2 is correct, since editing at the zygote or early embryo stage is precisely what was done in the 2018 episode in China, and the resulting change is heritable because it is present in every cell.
• Statement 3 is correct, since human induced pluripotent stem cells have been injected into pig embryos to create interspecies chimeras, work directed at eventual organ generation, though the contribution of human cells has remained very low. All three stand, giving (d). Each of options (a), (b) and (c) rests on treating one demonstrated capability as impossible. The general principle to teach here is that the question asks what can be done, not what is permitted.

• Statement 1 is correct. Streptococcus pneumoniae causes not only pneumonia but also bacterial meningitis, septicaemia and otitis media, and the conjugate vaccine protects against the invasive forms as well.
• Statement 2 is correct and is the antimicrobial resistance argument for vaccination. Preventing infection removes the occasion for antibiotic use, and pneumococcus has developed resistance to penicillins and macrolides, so reducing case load directly reduces reliance on drugs that are losing effectiveness.
• Statement 3 is incorrect and is disposed of by the absolute phrasing alone. No vaccine is free of adverse events; injection site reactions, fever and rare hypersensitivity occur with conjugate vaccines as with others. The answer is 1 and 2, giving (b).
• Options (c) and (d) fail on the no side effects claim and (a) drops the resistance argument.

• Statement 1 is correct. The cellulose wall external to the plasma membrane is the classic plant feature, absent in animal cells, which have only the membrane and an extracellular matrix.
• Statement 2 is incorrect and is decisive. Every living cell, plant, animal, fungal or bacterial, possesses a plasma membrane, since without it there is no cell; the plant cell has a wall in addition to the membrane, not instead of it.
• Statement 3 is correct. A mature plant cell is dominated by a single large central vacuole that maintains turgor and stores solutes, whereas animal cells contain small and transient vacuoles and vesicles. The answer is 1 and 3, giving (c).
• Options (a), (b) and (d) all admit the plasma membrane error, so recognising that single point settles the question.

Benzene is an aromatic hydrocarbon released chiefly by incomplete combustion and by evaporation of petroleum fuels.

• Statement 1 is correct, vehicle exhaust and fuel evaporation at pumps being the dominant outdoor source, which is why benzene content in petrol is regulated.
• Statement 2 is correct, tobacco smoke being the single largest source of personal exposure for smokers and a major indoor source for others.
• Statement 3 is correct, since biomass and wood burning release benzene along with other aromatics, a significant exposure route in households using solid fuels. The key treats statements 4 and 5 as incorrect, on the reasoning that benzene is not a constituent of cured polyurethane products and that furniture finishes are not a recognised benzene source in the standard listings. The keyed answer is 1, 2 and 3, giving (a).

• Statement 1 is correct. Short term external debt is the classic vulnerability, since it must be rolled over continuously and dries up first in a crisis, as the East Asian episode of 1997 demonstrated. Limiting reliance on it, alongside adequate reserve cover, is the standard prophylactic.
• Statement 2 is incorrect. A larger presence of foreign banks increases the channels through which stress abroad transmits into the domestic system, since parent institutions under pressure withdraw funding and cut exposures.
• Statement 3 is incorrect on two counts. India does not have full capital account convertibility, so it cannot be maintained, and the restrictions retained on debt flows are precisely what limits sudden stop risk; the Tarapore committees recommended a cautious and conditional approach for that reason. Only statement 1 stands, giving (a).

Narrow money is defined as currency with the public plus demand deposits with the banking system plus other deposits with the Reserve Bank. A cash withdrawal converts one component into another, reducing demand deposits by the amount withdrawn and increasing currency with the public by the same amount. The sum is unaffected, so (d) is correct.

• Option (a) is wrong because it counts only the fall in deposits and forgets that the notes in hand remain money.
• Option (b) is wrong for the mirror error.
• Option (c) is wrong because a multiplier effect greater than the initial sum arises on the deposit side when cash enters the banking system and is on lent, that is the reverse transaction, and even then the expansion is not immediate. The word immediate in the stem is doing the work, since a sustained drain of cash does reduce reserves and constrain later credit creation.

Foreign direct investment is equity investment carrying a lasting interest and a degree of management participation. Because the foreign investor takes an ownership stake rather than lending, there is no fixed repayment obligation and returns accrue only if the enterprise earns profits. This is precisely why it is classified as a non debt creating flow and is preferred over external commercial borrowing and portfolio debt, giving (b).

• Option (a) is wrong because listing is irrelevant; a great deal of foreign direct investment goes into unlisted and greenfield ventures, and investment through capital instruments in listed companies below the threshold is portfolio investment.
• Option (c) is wrong because debt servicing is the defining feature of external borrowing, the opposite of equity.
• Option (d) is wrong because purchases of government securities by foreign institutional investors are portfolio flows, and debt flows at that.

On the substance, statement 1 is correct, since India has run a merchandise trade deficit continuously, imports being dominated by crude oil, gold and electronics.

• Statement 3 is correct, since India is a net exporter of services, software and business services generating a surplus that offsets a large part of the goods deficit.
• Statement 2 is doubtful, since imports in those categories moved with the investment and commodity cycle rather than in one direction, and no stable recent decrease can be asserted.
• Statement 4 as printed conflates two different balances. India does run a persistent trade deficit, but the current account is a wider concept that includes the services surplus and remittances, and it has moved into surplus in some periods. The intended answer was therefore 1, 3 and 4, that is (d). The item was dropped, and this is the second and last dropped item in the paper.

West Texas Intermediate is a light, sweet crude oil, low in density and in sulphur, delivered at Cushing in Oklahoma, and it serves as the pricing benchmark for North American crude. The other principal benchmarks are Brent for the Atlantic basin and the Dubai and Oman basket, which matters most for India since the bulk of Indian imports are priced off it. Hence (a).

• Option (b) is wrong because bullion refers to gold and silver in bulk form and is graded by fineness.
• Option (c) is wrong because the rare earth elements are the fifteen lanthanides together with scandium and yttrium, traded as separated oxides rather than under regional grade names.
• Option (d) is wrong because uranium is classified by enrichment level and by chemical form, again with no such geographic grade nomenclature.

Under the separation plan that followed the India United States civil nuclear agreement of 2008, India divided its reactors into a civilian list and a strategic list. Reactors that use imported uranium, or that were built with foreign assistance, are placed on the civilian list and accept International Atomic Energy Agency safeguards, which verify that the fuel is not diverted to weapons use. Reactors running on domestically mined uranium remain outside safeguards, preserving freedom of action for the strategic programme. Hence (b).

• Option (a) is wrong because no Indian power reactor runs on thorium as primary fuel; thorium enters only in the third stage of the programme, and safeguards attach to fuel origin rather than fuel type.
• Option (c) is wrong because no reactor in India is operated by a foreign enterprise.
• Option (d) is wrong because there is no private ownership of reactors, operation resting with the Nuclear Power Corporation and Bhavini.

• Statement 1 is correct. The illustrative list annexed to the agreement treats trade balancing requirements and restrictions on a firm's imports linked to its exports or foreign exchange earnings as inconsistent with the prohibition on quantitative restrictions.
• Statement 2 is incorrect and is the discriminating statement. Article 1 confines the agreement to investment measures related to trade in goods alone; services are dealt with separately under the General Agreement on Trade in Services, whose commercial presence mode covers investment in services.
• Statement 3 is correct, and appears paradoxical only until the scope is understood. The agreement does not regulate foreign investment as such, since entry, ownership caps and sectoral conditions remain with the host state; it disciplines only those investment measures that distort trade in goods. The answer is 1 and 3, giving (c).

• Statement 1 is incorrect. Worker productivity measured at constant prices rose in rural as well as urban areas after liberalisation; the rural increase was slower, but it was an increase and not a decline.
• Statement 2 is incorrect and is the most useful eliminator, since structural transformation moves labour out of agriculture and out of the countryside, so the rural share of the workforce fell rather than rose.
• Statement 3 is correct, the expansion of rural construction, trade, transport and services being one of the defining features of the period and the main channel through which rural incomes diversified.
• Statement 4 is correct, since aggregate employment growth in rural areas slowed markedly, particularly in the decade after 2004 to 2005, the phenomenon discussed as jobless growth. The answer is 3 and 4, giving (b).
• Options (a) and (d) rest on the rural share error.

• Statement 1 is incorrect. Scheduled commercial banks dominate agricultural credit delivery in India and account for the large majority of the ground level credit flow, with cooperatives supplying a declining minority share and regional rural banks the remainder. The cooperative structure was the original vehicle for rural credit but lost primacy after bank nationalisation and the priority sector framework.
• Statement 2 is correct. District Central Cooperative Banks occupy the middle tier of the three tier short term cooperative structure, between the State Cooperative Bank above and the Primary Agricultural Credit Societies below, and refinancing the societies is their principal function. Only statement 2 stands, giving (b).
• Options (a) and (c) require accepting cooperative dominance, which the data contradict, and (d) discards a correct textbook description of the cooperative pyramid.

Cyber insurance responds to losses arising through the digital medium, and the organising principle is that the harm must be electronic in nature.

• Statement 1 is covered, restoration and data recovery after a malware or ransomware incident being a standard head.
• Statement 3 is covered, since consultant and negotiator fees in an extortion event fall under crisis response costs.
• Statement 4 is covered, third party liability and the cost of legal defence being a core component of any liability policy.
• Statement 2 is not covered and is the discriminating item, because wilful physical destruction of hardware is a property loss and belongs to a householder or all risks policy, not to a cyber policy. The answer is 1, 3 and 4, giving (b).
• Options (a), (c) and (d) all treat physical damage as a cyber risk, which confuses the medium of the loss with the object damaged.

The interest coverage ratio is earnings before interest and taxes divided by the interest expense, and it measures how many times over a firm's operating earnings can meet its interest obligation.

• Statement 1 is correct, since the ratio computed from current accounts gives a lender a direct reading of present repayment capacity.
• Statement 2 is correct, since the trend of the ratio across periods, and its behaviour under stressed assumptions, is the standard tool for judging emerging or prospective risk, a ratio near or below one signalling incipient distress.
• Statement 3 is incorrect and inverts the relationship, since a higher ratio means a larger cushion of earnings over interest and therefore a better, not worse, capacity to service debt. The answer is 1 and 2, giving (a).
• Options (c) and (d) admit the inversion, and (b) drops the correct present risk reading.

• Statement 1 is incorrect because of the word consistently. Indo Sri Lankan trade grew over the decade in broad terms but fell in several individual years, notably in the middle of the decade, so an unbroken increase cannot be asserted.
• Statement 2 is correct. Textiles dominate the bilateral basket, India exporting raw cotton and yarn that feed the Bangladeshi garment industry and importing finished garments and jute goods in return, which makes this the single most important trade relationship between the two economies.
• Statement 3 is incorrect and is the decisive error. Bangladesh, not Nepal, is India's largest trading partner within South Asia. Only statement 2 stands, giving (b).
• Options (a) and (d) admit the Sri Lanka claim and (c) and (d) admit the Nepal claim, so recognising either settles the question.

The G20 comprises nineteen countries together with the European Union, and among the developing and emerging economies it includes Argentina, Mexico, South Africa and Turkey, so (a) is correct.

• Option (b) fails on Malaysia and New Zealand, neither of which is a member although Australia and Canada are.
• Option (c) fails on Iran and Vietnam; Brazil and Saudi Arabia are members but Iran is not part of the grouping at all and Vietnam attends only when invited.
• Option (d) fails on Singapore, which is a standing invitee through its chairmanship of the Global Governance Group rather than a member, while Indonesia, Japan and South Korea are members. The question rewards knowing that regular guests such as Singapore, Spain and the Netherlands are not to be counted as members.

• Statement 1 is correct. Food and beverages carry a weight of about forty six per cent in the combined Consumer Price Index against roughly a quarter for food in the Wholesale Price Index, which is why retail inflation is so sensitive to vegetable and pulse prices.
• Statement 2 is correct. The Wholesale Price Index covers only goods transacted in bulk at the first point of sale, whereas the Consumer Price Index includes housing, education, health, transport and recreation, all of which are services.
• Statement 3 is incorrect and reverses the actual position. Following the Urjit Patel committee, the Reserve Bank adopted the Consumer Price Index as its nominal anchor in 2014, and the flexible inflation targeting framework introduced in 2016 fixes the target of four per cent with a band of two percentage points on the combined Consumer Price Index. The answer is 1 and 2, giving (a).

• Pair 1 is incorrect. The Mekong rises on the Tibetan plateau, runs through China, Myanmar, Laos, Thailand and Cambodia and empties through its delta in southern Vietnam into the South China Sea; the Irrawaddy and Salween are the rivers that reach the Andaman Sea.
• Pair 2 is incorrect. The Thames flows eastward through London and enters the North Sea through its estuary, the Irish Sea lying to the west of Britain and receiving the Mersey and the Severn by way of the Bristol Channel.
• Pair 3 is correct, the Volga being the longest river in Europe and draining into the Caspian, an inland basin, which is why it is a river of internal drainage.
• Pair 4 is correct, the Zambezi crossing southern Africa past the Victoria Falls and reaching the Indian Ocean through Mozambique. The answer is 3 and 4, giving (c).

• Statement 1 is incorrect. Open ended procurement in practice operates chiefly for paddy and wheat, and mainly in the surplus states of Punjab, Haryana, Madhya Pradesh and Telangana. For pulses and oilseeds procurement runs through the Price Support Scheme with ceilings on the quantity that may be bought, typically a fixed proportion of production, so it is neither universal nor unlimited.
• Statement 2 is incorrect on its own logic. The Minimum Support Price is a floor calculated with reference to the cost of production, and market prices routinely exceed it; if the market price could never rise to the support level the price would function as a ceiling, which is the opposite of its purpose. Neither statement stands, giving (d).
• Options (a), (b) and (c) each accept one of two claims that the word never and the word unlimited make untenable.

• Statement 1 is correct. Commercial paper is an unsecured money market instrument issued in the form of a promissory note by corporates, primary dealers and financial institutions to raise short term funds, sold at a discount to face value.
• Statement 2 is incorrect on two counts. A certificate of deposit is a short term instrument, with tenor from seven days to one year for banks, and it is issued by banks and select financial institutions to depositors, not by the Reserve Bank to a corporation.
• Statement 3 is correct. Call money is uncollateralised overnight lending in the interbank market, the rate on which is the operating target of monetary policy.
• Statement 4 is incorrect, since zero coupon bonds by definition pay no periodic interest and are issued at a discount, redemption at par supplying the entire return. The answer is 1 and 3, giving (c). Every wrong option carries statement 2 or statement 4.

• Pair 1 is correct. Parivrajaka denotes one who has gone forth, the wandering renunciant who has abandoned household life, the term being used across the Brahmanical, Buddhist and Jain traditions and appearing also as a dynastic title in the Gupta period.
• Pair 2 is incorrect and is the discriminating item. Shramana means one who strives or exerts, and denotes the ascetic of the non Vedic traditions, Buddhist, Jain and Ajivika. The shramana stands in explicit opposition to the brahmana, the priest of high ritual status, and the two words name the two rival streams of early Indian religious life.
• Pair 3 is correct, upasaka being the lay male devotee who takes refuge and observes the precepts without entering the order, the female counterpart being upasika. The answer is 1 and 3, giving (b).

• Statement 1 is correct. Elephant herds are matriarchal, the oldest and most experienced cow leading the group, while adult bulls leave the natal herd and live singly or in loose bachelor associations.
• Statement 2 is correct. Gestation ranges from about eighteen to twenty two months, the longest of any land mammal, a consequence of the prolonged brain development of the calf.
• Statement 3 is incorrect. Cows continue to breed well past forty and into their sixties, and the presence of post reproductive as well as breeding older females is central to herd knowledge and survival.
• Statement 4 is incorrect. Karnataka holds the largest elephant population among Indian states, followed by Assam, with Kerala third. The answer is 1 and 2, giving (a).
• Options (b) and (d) rest on the Kerala claim and (c) and (d) on the calving age claim.

The hard ground barasingha, Rucervus duvaucelii branderi, is the central Indian subspecies whose hooves are adapted to firm rather than marshy terrain and which grazes almost exclusively on grasses. Kanha is its last natural stronghold and the site of the recovery that brought it back from a few dozen animals, which is why it is the state animal of Madhya Pradesh and the park mascot, giving (a).

• Option (b) is wrong because Manas holds the eastern swamp deer, a distinct subspecies of the wet terai and floodplain.
• Option (c) is wrong because Mudumalai in the Nilgiris is known for elephant, gaur and tiger and lies outside the swamp deer range entirely.
• Option (d) is wrong because Tal Chhapar in the Rajasthan desert is a blackbuck sanctuary on saline flat grassland.

Steel slag is the calcium silicate rich residue of steelmaking and all three uses are established, giving (d).

• Statement 1 is correct because processed slag aggregate is hard, angular and abrasion resistant, and it is used in base and sub base courses of roads, the Indian Road Congress having issued guidelines for steel slag road construction.
• Statement 2 is correct because slag is alkaline and supplies calcium, magnesium and silicon, so it functions as a liming agent to correct acidic soils and as a silicate source for crops such as rice.
• Statement 3 is correct because ground granulated blast furnace slag is a standard supplementary cementitious material used to make Portland slag cement, which also lowers the clinker requirement and therefore the emissions of the cement.
• Options (a), (b) and (c) each discard one valid route. The governing principle is circularity, industrial residue substituting for virgin material.

• Statement 1 is correct. Coal contains trace heavy metals which are concentrated in the ash on combustion, and arsenic, lead, mercury, selenium and chromium leach from unlined ash ponds into groundwater, the reason fly ash disposal is regulated and its utilisation mandated.
• Statement 2 is correct. Sulphur in the fuel oxidises to sulphur dioxide and atmospheric nitrogen oxidises at flame temperature to oxides of nitrogen, the two precursors of acid deposition and of secondary particulate matter, which is why flue gas desulphurisation was mandated for Indian thermal plants.
• Statement 3 is correct. Indian coal is of drift origin and carries an ash content commonly in the range of thirty to forty five per cent, though it is low in sulphur, which is the compensating feature. All three stand, giving (d). Each of options (a), (b) and (c) requires denying one uncontroversial fact about Indian thermal generation.

Biochar is the stable carbon rich solid left when biomass is pyrolysed in the near absence of oxygen, and its agronomic value flows from a single physical property, an extremely large internal pore structure and surface area.

• Statement 1 is correct, since that structure makes it a light, inert and durable component of soilless growing media, including in vertical and container systems.
• Statement 2 is correct, since the pores shelter microbial colonies from predation and desiccation and the material adsorbs and slowly releases nutrients, conditions under which nitrogen fixing and other beneficial organisms proliferate.
• Statement 3 is correct, since the same porosity holds water against gravity and releases it slowly, raising the water holding capacity of the medium. All three stand, giving (d). The wider significance, which the question does not test but which matters for the climate discussion, is that biochar also locks carbon in a form that resists decomposition for centuries.

Schedule VI was inserted by the amendment of 1991 and is the only schedule of the Act dealing with plants. It lists six specified species, among them the pitcher plant, blue vanda, red vanda, the lady's slipper orchid, Beddome's cycad and kuth. The effect of listing is regulatory rather than prohibitory. No person may cultivate, possess, sell or transport a listed plant without a licence from the Chief Wildlife Warden, which permits legitimate cultivation and propagation while allowing wild collection to be controlled. Hence (a).

• Option (b) is wrong precisely because licensed cultivation is contemplated and encouraged, since cultivation reduces pressure on wild populations.
• Option (c) is wrong because genetically modified organisms are regulated under the Environment Protection Act rules of 1989 through the Genetic Engineering Appraisal Committee.
• Option (d) is wrong because the schedule protects rare and threatened species, not invasive ones.

All three are coastal sites and all three appear in the record of maritime commerce, giving (a). Ghantasala lies in the Krishna delta of Andhra Pradesh and served the eastern seaboard trade with Southeast Asia, its Buddhist stupa reflecting the association of merchants with the sangha. Kadura is a port of the western Deccan coast named in the classical accounts of Indian Ocean trade. Chaul lies on the Konkan coast south of Mumbai and remained an active port from the early centuries of the common era down to the Portuguese period.

• Option (b) is wrong because none was a dynastic capital, the Gupta and contemporary capitals being Pataliputra, Ujjain, Vatapi and Kanchi.
• Option (c) is wrong because these are commercial rather than monumental sites.
• Option (d) is wrong because, although Ghantasala carries Buddhist remains, that is incidental to the common feature the question asks for, and Chaul and Kadura are not pilgrimage centres.

Zero tillage means placing seed directly into undisturbed soil through the residue of the previous crop.

• Statement 1 is correct and is the practical answer to stubble burning in the north western plains, since the happy seeder and similar drills sow wheat straight through standing and loose paddy straw, removing the reason to burn it and shortening the turnaround between crops.
• Statement 2 is correct, since direct seeded rice dispenses with the nursery, puddling and transplanting sequence and saves both water and labour.
• Statement 3 is correct, because tillage aerates the soil and accelerates oxidation of organic matter, so leaving the soil undisturbed and the residue on the surface builds soil organic carbon instead of releasing it. All three stand, giving (d).
• Options (a), (b) and (c) each reject one well documented benefit of a single coherent practice.

The National Policy on Biofuels of 2018 widened the feedstock base for ethanol to sugar containing materials such as sugar beet and sweet sorghum, starch containing materials such as corn and cassava, and damaged food grains and other produce unfit for human consumption, including rotten potatoes.

• Statements 1, 2, 5 and 6 therefore qualify, giving (a).
• Statement 3 is excluded because groundnut is an edible oilseed and the policy deliberately keeps food grade edible oil out of the biodiesel stream, restricting biodiesel to non edible oilseeds, used cooking oil and short gestation crops.
• Statement 4 is excluded because horse gram is a pulse consumed as food and fodder and appears nowhere in the permitted list.
• Options (b), (c) and (d) all admit at least one edible commodity. The governing principle is that biofuel policy avoids diverting sound human food, permitting only unfit, surplus or non edible material.

The social cost of carbon is the present value of the total future damage caused by emitting one additional tonne of carbon dioxide in a given year, aggregated across agriculture, health, sea level rise, productivity and ecosystem loss and discounted to today. Its purpose is to internalise an externality by putting a number on harm that the emitter does not otherwise pay for, and it is used in regulatory cost benefit analysis and in setting carbon prices. Hence (a).

• Option (b) describes energy demand or fossil fuel intensity, a measure of consumption rather than of damage.
• Option (c) describes adaptation cost borne by a displaced person, which is one component of the damage but not the concept.
• Option (d) describes an individual carbon footprint, which measures emissions in tonnes rather than harm in money. The distinguishing features to teach are the unit of one tonne, the reference to a given year and the long term horizon.

• Statement 1 is correct. Black gram, urad, is short duration and photo insensitive enough to be grown in the kharif season across central and southern India and as a rabi or summer crop in the rice fallows of the south and east, and it is also raised as a summer catch crop in the north.
• Statement 2 is incorrect and is the discriminating statement. The pulse that accounts for roughly forty to fifty per cent of Indian production is gram, that is chana, a rabi crop; green gram, moong, contributes under a tenth.
• Statement 3 is incorrect. Rabi pulses have not declined; gram production expanded substantially over the period, particularly with the shift of the crop from the northern plains to Madhya Pradesh, Rajasthan and Maharashtra, and rabi continues to supply the larger share of the total. Only statement 1 stands, giving (a).

The description matches cotton on every count, giving (a). Cotton is grown in the subtropical belt, is destroyed by frost, requires a long frost free period of about two hundred and ten days for the boll to mature, and does well on the moderate rainfall of fifty to one hundred centimetres characteristic of the Deccan and Gujarat, the black regur soil retaining moisture through the dry spell.

• Option (b) is wrong because jute needs heavy rainfall of about one hundred and fifty to two hundred centimetres with high humidity and grows on the alluvium of the Ganga Brahmaputra delta.
• Option (c) is wrong because sugarcane is tropical, needs a longer growing period of ten to fifteen months and tolerates heavier soils.
• Option (d) is wrong because tea requires high rainfall and well drained sloping ground and is a plantation shrub rather than a field crop. The rainfall figure alone eliminates jute and tea, and the word subtropical eliminates sugarcane.

The reasoning here is first principles rather than recall. Solar photovoltaic panels supply electricity, and once electricity is available the pump does not know or care where it came from. What the panel constrains is the power available and its variation through the day, not the type of pump.

• Statement 1 is therefore incorrect, and solar submersible pumps are in fact the commoner configuration in India because groundwater tables lie below the suction limit of a surface pump.
• Statement 2 is incorrect for the same reason. Centrifugal pumps are usual because they suit continuously variable speed drives, but positive displacement pumps including piston and helical rotor types are used with solar arrays, and they are preferred at low flow and high head. Neither statement stands, giving (d).
• Options (a), (b) and (c) all treat the energy source as though it dictated the mechanical design.

• Statement 1 is correct. In the bud chip method only the bud along with a small portion of adjoining cane is scooped out and raised in a nursery, so the remaining cane is available for milling, and seed material requirement falls sharply against conventional planting of two or three budded setts.
• Statement 4 is correct. Micropropagation from meristem tissue is used to multiply disease free planting material rapidly and is standard in seed cane programmes.
• Statements 2 and 3 are both incorrect and both invert the underlying agronomy. A sett with several buds carries more stored food and moisture in the internodes, so it germinates at a higher percentage and survives adverse weather better than a single budded sett, which has a small reserve and desiccates or rots more readily. The answer is 1 and 4, giving (c). The single budded sett is chosen to economise on seed, not because it establishes better, and options (a), (b) and (d) all confuse those two things.

• Statement 1 is correct, since moving away from the paddy and wheat monoculture reduces the drawdown of groundwater, breaks pest and disease cycles and restores nutrient balance.
• Statement 2 is correct, since legumes fix atmospheric nitrogen through rhizobial symbiosis and cut the requirement for synthetic urea, which is the largest single source of emissions and of nitrate leaching in Indian farming.
• Statement 3 is correct, since a tensiometer measures soil moisture tension and tells the farmer when irrigation is actually needed, avoiding over watering and the waterlogging and salinity that follow.
• Statement 4 is excluded by the key, on the reasoning that vertical farming in controlled environments depends on artificial lighting, climate control and continuous power, so its energy footprint offsets the saving in land and water, and it is in any case a niche horticultural technique rather than a field practice in the Indian context. The answer is 1, 2 and 3, giving (a).

Fertigation is the delivery of dissolved fertiliser through the irrigation system, usually drip, and the constraint that governs the whole question is solubility.

• Statement 2 is therefore incorrect and is the discriminating statement. Rock phosphate is an insoluble mineral that must be acidulated before the phosphorus becomes available, and it would block emitters rather than pass through them, so the claim that all other phosphatic fertilisers can be applied efficiently is also too wide.
• Statement 1 is correct, since acidic fertilisers such as phosphoric acid or ammonium sulphate injected into the line neutralise alkalinity and prevent carbonate scaling of the drippers.
• Statement 3 is correct, since nutrients are delivered in solution directly into the wetted root zone in small and frequent doses matched to crop demand.
• Statement 4 is correct, since applying small quantities repeatedly, rather than broadcasting a large dose, leaves little surplus to move below the root zone. The answer is 1, 3 and 4, giving (c).

• Statement 2 is correct and is the substance of the research the question draws on. Ocean Mean Temperature integrates heat through the upper ocean layer rather than sampling only the skin, so it captures the heat content actually available to drive convection, and the January to March value in the south western Indian Ocean has been shown to predict whether the following monsoon will be above or below the long period average with greater accuracy than sea surface temperature.
• Statement 1 is treated as incorrect by the official key. The keyed answer is therefore 2 only, giving (b), with (a) and (d) rejected outright and (c) rejected only on the treatment of statement 1.

• Statement 1 is incorrect and is the discriminating statement. The maximum retail price of urea remains statutorily controlled and the gap between cost and that price is met by subsidy, while phosphatic and potassic fertilisers were decontrolled in price under the nutrient based subsidy regime of 2010 but remain under a fixed per nutrient subsidy and informal price monitoring. The blanket claim that fertiliser prices are market driven is therefore wrong, and urea alone defeats it.
• Statement 2 is correct. Ammonia is synthesised by the Haber Bosch process from nitrogen and hydrogen, and the hydrogen is obtained by steam reforming of natural gas, which is why urea economics track gas prices and why gas pooling was introduced for fertiliser plants.
• Statement 3 is correct. Sulphur recovered during the desulphurisation of crude at refineries is burnt to sulphur dioxide and converted to sulphuric acid, which digests rock phosphate to give phosphoric acid. The answer is 2 and 3, giving (b).

• Statement 1 is correct. The Desert National Park extends across the Jaisalmer and Barmer districts of Rajasthan and is among the largest protected areas in India, covering roughly three thousand one hundred and sixty square kilometres of sand dune, sewan grassland and salt flat.
• Statement 3 is correct and is the reason the park matters, since it holds the largest surviving population of the great Indian bustard, a critically endangered species whose principal threat is now collision with overhead power lines crossing its habitat.
• Statement 2 is incorrect and is the discriminating statement. A substantial resident population lives inside the park in a number of villages, grazing livestock on the same grassland, and this coexistence is precisely the management problem that has dogged the park since notification. The answer is 1 and 3, giving (c).
• Options (a), (b) and (d) all accept the claim of no habitation, which no large Indian protected area in an inhabited desert could satisfy.

The Siachen glacier lies in the eastern Karakoram, and its meltwater feeds the Nubra river, which flows south from the glacier snout to join the Shyok. The glacier therefore lies at the head of and to the north of the Nubra valley, giving (d).

• Option (a) is wrong because Aksai Chin lies far to the east, on the Tibetan plateau margin, so Siachen is west of it rather than the reverse.
• Option (b) is wrong because Leh lies to the south, on the Indus, and the route to the glacier runs north from Leh over the Khardung La into the Nubra valley.
• Option (c) is wrong because Gilgit lies well to the west in the territory held by Pakistan, so the glacier is to its east. Fixing the Nubra valley on the mental map is the single step that answers the question, since the glacier and the valley form one continuous drainage line.

• Pair 1 is correct. Bhilsa is the old name of Vidisha in Madhya Pradesh, near Sanchi and Udayagiri, a town of importance from Mauryan times.
• Pair 3 is correct. Girinagar is Junagadh in Gujarat, the site at the foot of Girnar bearing the Ashokan rock edicts, the Rudradaman inscription on the Sudarshana lake and the later Skandagupta inscription, one of the richest epigraphic sites in India.
• Pair 2 is incorrect. Dwarasamudra is Halebidu in Karnataka, the capital of the Hoysalas, sacked by Malik Kafur, and it lies nowhere near Maharashtra.
• Pair 4 is incorrect. Sthanesvara is Thanesar in Haryana, the seat of the Pushyabhuti dynasty from which Harshavardhana came before shifting to Kanauj, which is the Uttar Pradesh town the option is presumably meant to confuse it with. The answer is 1 and 3, giving (a).

• Statement 2 is correct. The Central Ground Water Authority was constituted in 1997 under section 3 of the Environment Protection Act of 1986, on the direction of the Supreme Court, and it draws its regulatory power to notify and restrict extraction from that statute rather than from any dedicated groundwater law.
• Statement 3 is correct. India irrigates more land from groundwater than any other country, ahead of China and the United States, the tubewell having displaced canal and tank irrigation since the green revolution.
• Statement 1 is treated as incorrect. Assessment is carried out by unit, that is by block, taluka or mandal rather than by district, and the proportion falling in the overexploited and critical categories is materially lower than thirty six per cent, though it rises if the semi critical category is added. The answer is 2 and 3, giving (b).

• Statement 1 is incorrect. Jet streams are a consequence of the thermal gradient between equator and pole and of the Coriolis deflection, both of which operate in both hemispheres, so polar front and subtropical jets exist north and south of the equator.
• Statement 2 is correct. The eye is a feature of intense and well organised tropical cyclones, appearing once the system is mature and the circulation symmetric; weaker tropical storms, and the extratropical and temperate cyclones which form on fronts, have no eye at all.
• Statement 3 is incorrect and is the discriminating statement. The eye is the warmest part of the storm, not the coldest, because air subsides in the centre and warms adiabatically as it descends, which is exactly why the eye is cloud free and calm; the warm core is what distinguishes a tropical cyclone from a temperate one. Only statement 2 stands, giving (c). The physical reasoning on subsidence disposes of statement 3 without any recall of figures.

Critical tiger habitat is the core area of a tiger reserve, notified under the Wild Life Protection Act on the advice of an expert committee and required to be kept inviolate. Nagarjunsagar Srisailam, straddling Andhra Pradesh and Telangana in the Nallamala hills along the Krishna, is the largest tiger reserve in India and has the largest notified core, of the order of two and a half thousand square kilometres, giving (c).

• Option (a) is wrong because Corbett, though the oldest and among the densest in tiger numbers, has a core of about eight hundred square kilometres.
• Option (b) is wrong because Ranthambore's core is of the order of eleven hundred square kilometres.
• Option (d) is wrong because the Sunderbans core, at about seventeen hundred square kilometres, is large but still smaller than Nagarjunsagar Srisailam. The trap is that the three wrong options are the more famous reserves, while the correct answer is the largest but least celebrated.