UPSC Prelims 2023 previous year paper · official paper and PYQ-pattern practice

UPSC Prelims 2023 PYQ-pattern questions

Showing 10 of the 19 PYQ-pattern questions in this set — freshly worded in that year's pattern, not the original questions. Answers and solutions open under each question.

1. Q1 · Indian and World Geography — Physical, Social, Economic

   Consider the following pairs of rivers and their tributaries: 1. Ganga - Yamuna 2. Godavari - Indravati 3. Krishna - Tungabhadra 4. Narmada - Tapi How many pairs given above are correctly matched?

   • A. Only one pair
   • B. Only two pairs
   • C. Only three pairs
   • D. All four pairs
   Answer and solution

   Answer: C

   Pairs 1, 2, and 3 are correctly matched. Yamuna is a major tributary of Ganga, Indravati is a tributary of Godavari, and Tungabhadra is a tributary of Krishna. However, pair 4 is incorrect; Tapi is not a tributary of Narmada but an independent river flowing parallel to it in central India.

2. Q2 · General Science

   Consider the following statements regarding CRISPR-Cas9 technology: 1. It is a gene-editing tool that allows scientists to alter DNA sequences and modify gene function. 2. The technology uses RNA molecules to guide the Cas9 enzyme to specific DNA sequences. 3. CRISPR technology has been successfully used in treating sickle cell disease in clinical trials. Which of the statements given above is/are correct?

   • A. 1 only
   • B. 1 and 2 only
   • C. 2 and 3 only
   • D. 1, 2 and 3
   Answer and solution

   Answer: D

   All three statements are correct. CRISPR-Cas9 is a revolutionary gene-editing technology that uses guide RNA to direct the Cas9 enzyme to specific DNA locations for precise editing. It has shown remarkable success in clinical trials for treating genetic diseases including sickle cell disease, representing a major breakthrough in medical science.

3. Q3 · Indian and World Geography — Physical, Social, Economic

   Consider the following pairs of ocean currents and their characteristics: 1. Kuroshio Current – Warm current in the North Pacific Ocean 2. Benguela Current – Cold current along the western coast of Africa 3. Brazil Current – Cold current in the South Atlantic Ocean How many of the above pairs is/are correctly matched?

   • A. Only one
   • B. Only two
   • C. All three
   • D. None
   Answer and solution

   Answer: B

   Pair 1 is correct: Kuroshio is a warm current flowing northeast along Japan's coast. Pair 2 is correct: Benguela is a cold current along southwestern Africa. Pair 3 is incorrect: Brazil Current is a warm current flowing southward along Brazil's eastern coast, not a cold current.

4. Q4 · Indian Polity and Governance — Constitution, Political System, Panchayati Raj, Public Policy, Rights Issues

   With reference to the 'Anti-Defection Law' in India, consider the following statements: 1. A member who voluntarily gives up membership of their political party is disqualified. 2. The decision of the Presiding Officer on disqualification is final and cannot be challenged in any court. 3. Independent members who join any political party after election are not subject to disqualification. Which of the statements given above is/are correct?

   • A. 1 only
   • B. 1 and 2 only
   • C. 2 and 3 only
   • D. 1 and 3 only
   Answer and solution

   Answer: A

   Statement 1 is correct: Under the Tenth Schedule, voluntary resignation from party leads to disqualification. Statement 2 is incorrect: The Supreme Court has held that decisions of the Presiding Officer are subject to judicial review. Statement 3 is incorrect: Independent members joining any party after election are disqualified under the anti-defection provisions.

5. Q5 · Environmental Ecology, Biodiversity and Climate Change

   With reference to the Ramsar Convention, consider the following statements: 1. It is an intergovernmental treaty that provides the framework for national action and international cooperation for the conservation of wetlands. 2. The convention allows a country to designate only one Ramsar site within its territory. 3. India has the highest number of Ramsar sites in South Asia. Which of the statements given above is/are correct?

   • A. 1 only
   • B. 1 and 3 only
   • C. 2 and 3 only
   • D. 1, 2 and 3
   Answer and solution

   Answer: B

   Statement 1 is correct - the Ramsar Convention provides a framework for wetland conservation. Statement 2 is incorrect - countries can designate multiple Ramsar sites. Statement 3 is correct - India has the most Ramsar sites in South Asia (over 80 as of recent designations).

6. Q6 · Indian Polity and Governance — Constitution, Political System, Panchayati Raj, Public Policy, Rights Issues

   Which of the following constitutional bodies is/are mentioned in the Constitution of India? 1. Finance Commission 2. National Human Rights Commission 3. Election Commission How many of the above are correctly stated?

   • A. Only one
   • B. Only two
   • C. All three
   • D. None
   Answer and solution

   Answer: B

   Finance Commission (Article 280) and Election Commission (Article 324) are constitutional bodies mentioned in the Constitution. National Human Rights Commission is a statutory body established by the Protection of Human Rights Act, 1993, not mentioned in the Constitution. Hence, two are correctly stated.

7. Q7 · Environmental Ecology, Biodiversity and Climate Change

   Consider the following pairs of protected areas and their locations: 1. Dachigam National Park — Jammu and Kashmir 2. Papikonda National Park — Andhra Pradesh 3. Namdapha National Park — Arunachal Pradesh 4. Nokrek Biosphere Reserve — Meghalaya How many of the above pairs is/are correctly matched?

   • A. Only one pair
   • B. Only two pairs
   • C. Only three pairs
   • D. All four pairs
   Answer and solution

   Answer: D

   All four pairs are correctly matched. Dachigam is in J&K (known for Hangul deer), Papikonda is in Andhra Pradesh, Namdapha is in Arunachal Pradesh, and Nokrek is in Meghalaya (known for citrus gene pool).

8. Q8 · General Science

   Which of the following is the primary function of the Large Hadron Collider (LHC)?

   • A. To study cosmic radiation and dark matter from outer space
   • B. To accelerate particles to high energies and study fundamental particles and forces
   • C. To detect gravitational waves from distant black holes and neutron stars
   • D. To simulate nuclear fusion reactions for clean energy production
   Answer and solution

   Answer: B

   The Large Hadron Collider, located at CERN, accelerates particles to near-light speeds and collides them to study fundamental particles, forces, and phenomena like the Higgs boson.

9. Q9 · General Science

   With reference to DNA barcoding technology, consider the following: 1. It helps in the rapid identification of species using short genetic markers. 2. It can be used to detect adulteration in processed food products. 3. The technology relies on sequencing a segment of the mitochondrial genome. Which of the statements given above is/are correct?

   • A. 1 only
   • B. 1 and 2 only
   • C. 2 and 3 only
   • D. 1, 2 and 3
   Answer and solution

   Answer: D

   DNA barcoding uses short mitochondrial DNA sequences to identify species, detect food adulteration, and distinguish between similar-looking organisms.

10. Q10 · Economic and Social Development

    Which one of the following best describes the term 'legal tender money'?

    • A. Money tendered in courts of law to settle legal fees
    • B. Money that a creditor is compelled by law to accept in settlement of debt
    • C. Only metallic coins issued by the government mint
    • D. Bank money in the form of cheques and drafts
    Answer and solution

    Answer: B

    Legal tender is currency that must be accepted by law in payment of debts. Creditors cannot refuse it as a form of settlement.