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Home » UPSC Prelims Quiz » UPSC Prelims Quiz: October 13, 2025

UPSC Prelims Quiz: October 13, 2025

Q1. Consider the following statements:

I. Solar dimming over India is mainly caused by aerosols.

II. Twomey effect increases cloud brightness.

III. North Indian plains show maximum decline in sunshine hours.

Which of the statements given above are correct?

(a)

I and II only

(b)

II and III only

(c)

I and III only

(d)

I, II and III

Explanation

S1 – Correct: Aerosols from industry, vehicles, and biomass burning scatter sunlight, leading to long-term solar dimming.

S2 – Correct: Twomey effect makes clouds brighter by creating smaller droplets, reflecting more sunlight.

S3 – Correct: The steepest decline (≈ –13.1 hours/year) is recorded over the north Indian plains.

Answer: (d)
Q2. Consider the following statements regarding the Polar Silk Road:

I. It is part of China’s Belt and Road Initiative.

II. The Istanbul Bridge became the first cargo vessel to traverse the route.

III. It follows the Northern Sea Route along Russia’s Arctic coast.

Which of the statements given above are correct?

(a)

I and II only

(b)

II and III only

(c)

I and III only

(d)

I, II and III

Explanation

Statement I – Correct: The Polar Silk Road (PSR) is a strategic extension of China’s Belt and Road Initiative (BRI) to develop Arctic shipping routes.

Statement II – Correct: The Istanbul Bridge was the first cargo vessel to traverse the Polar Silk Road route in 2025, linking China and Europe via the Arctic.

Statement III – Correct: The PSR primarily follows the Northern Sea Route (NSR) along Russia’s Arctic coast, offering a shorter path between East Asia and Western Europe than the Suez Canal.

Answer: (d)
Q3. Which of the following statements is true about Operation HAECHI-VI?
(a)

It is an Interpol-led operation supported by the Republic of Korea to combat cyber-enabled financial crimes.

(b)

It is a Europol initiative focused on child exploitation networks in Europe.

(c)

It is a NATO mission to secure communication systems from cyberattacks.

(d)

It is a United Nations programme for digital literacy in developing countries.

Explanation

Operation HAECHI-VI is the sixth phase of Interpol’s global campaign against cyber-enabled financial crimes, such as investment fraud, online sextortion, romance scams, and voice phishing.

It is financially supported by the Republic of Korea and involves agencies worldwide, including the CBI, which arrested eight operatives in India.

Answer: (a)
Q4. Regarding species recently prioritized for conservation in Tamil Nadu, consider the following statements:

I. Lion-tailed macaque is an endemic primate of the Western Ghats.

II. Madras hedgehog is a nocturnal mammal adapted to dry scrub habitats.

III. Hump-headed mahseer is a freshwater fish native to Himalayan rivers.

Which of the statements given above are correct?

(a)

I and II only

(b)

II and III only

(c)

I and III only

(d)

I, II and III

Explanation

S1 – Correct: The lion-tailed macaque (Macaca silenus) is endemic to the Western Ghats and listed as Endangered under the IUCN Red List.

S2 – Correct: The Madras hedgehog (Paraechinus nudiventris) is a nocturnal insectivore found in dry scrub and thorn forests of Tamil Nadu and adjoining regions.

S3 – Incorrect: The hump-headed mahseer (Tor mussullah) is found in southern peninsular rivers like Cauvery and Kabini, not in Himalayan rivers.

Answer: (a) I and II only
Tamil Nadu’s New Initiative for Lesser-Known Species

Tamil Nadu has sanctioned ₹1 crore for conserving four lesser-known species — the lion-tailed macaque, Madras hedgehog, striped hyena, and hump-headed mahseer. The scheme broadens conservation beyond flagship animals such as tigers and elephants.

Funding Allocation:
₹48.5 lakh Lion-tailed macaque
₹20.5 lakh Madras hedgehog
₹14 lakh Striped hyena
₹17 lakh Hump-headed mahseer
Species Details:
  • Lion-tailed macaque: Endangered primate endemic to the Western Ghats; surviving in fragmented rainforest habitats.
  • Madras hedgehog: Nocturnal mammal native to semi-arid regions of Tamil Nadu, Andhra Pradesh, and Kerala; listed as Least Concern by IUCN.
  • Striped hyena: Near-threatened scavenger with localized decline around the Mudumalai region.
  • Hump-headed mahseer: Critically Endangered freshwater fish found in the Moyar River system; impacted by habitat degradation and overfishing.
Conservation Focus:
  • Habitat monitoring and population surveys.
  • Community awareness and staff training.
  • Conservation breeding and in-situ measures.
  • Canopy bridges for macaques; in-situ breeding for mahseer.
Broader Goal: The initiative aligns with the Kunming–Montreal Global Biodiversity Framework (30×30) to strengthen Tamil Nadu’s biodiversity conservation by 2030.
Q5. With reference to the National Payments Corporation of India (NPCI), consider the following statements:

1. It was established under the Banking Regulation Act, 1949, as a public limited company.

2. It operates the Immediate Payment Service (IMPS) as well as the National Automated Clearing House (NACH).

3. NPCI Bharat BillPay Limited and NPCI International Payments Limited are both its subsidiaries.

How many of the above statements are correct?

(a)

Only one

(b)

Only two

(c)

All three

(d)

None

Explanation

Statement 1 — Incorrect: NPCI was established in 2008 under the Payment and Settlement Systems Act, 2007 as a Section 8 (not-for-profit) company, not under the Banking Regulation Act.

Statement 2 — Correct: IMPS and NACH are both operated by NPCI as part of the domestic retail payments architecture.

Statement 3 — Correct: NPCI Bharat BillPay Limited (NBBL) and NPCI International Payments Limited (NIPL) are fully owned subsidiaries managing BBPS and international UPI/RuPay operations respectively.

→ Hence, two statements are correct.

Answer: (b) Only two
Q6. With reference to the 2025 operational guidelines issued by NPCI for UPI participants, consider the following:

1. Every successful UPI transaction must display the user’s updated account balance in the confirmation message.

2. Autopay transactions under UPI are restricted only to the morning hours between 6:00 AM and 10:00 AM.

3. Each user can make a maximum of fifty balance enquiries per app per day.

How many of the statements given above are correct?

(a)

Only one

(b)

Only two

(c)

All three

(d)

None

Explanation

Statement 1 — Correct: New rule (Aug 2025) mandates inclusion of the updated account balance in the confirmation message for transparency.

Statement 2 — Incorrect: UPI Autopay is restricted during peak hours (10:00–13:00 and 17:00–21:30), not limited to those hours.

Statement 3 — Correct: NPCI has capped balance enquiries to 50 per app per user per 24 hours.

→ Two statements are correct.

Answer: (b) Only two
Q7. With reference to Carbon Capture and Storage (CCS) technologies, consider the following statements:

1. In post-combustion capture, carbon dioxide is separated before the fossil fuel is burned.

2. Oxy-fuel combustion captures carbon dioxide directly from ambient air rather than from flue gases.

3. Direct Air Capture (DAC) requires combustion of fossil fuels in oxygen to increase CO₂ concentration.

How many of the statements given above are correct?

(a)

Only one

(b)

Only two

(c)

All three

(d)

None

Explanation

Statement 1 – Incorrect: Post-combustion capture removes CO₂ after fossil fuel combustion from flue gases, not before combustion.

Statement 2 – Incorrect: Oxy-fuel combustion burns fossil fuels in oxygen to produce a concentrated CO₂ stream — it does not capture CO₂ directly from ambient air.

Statement 3 – Incorrect: Direct Air Capture (DAC) extracts CO₂ directly from the atmosphere using chemical sorbents; it does not involve combustion of fossil fuels.

Answer: (d) None
Q8. In the context of medical research, the term “T-cell therapy” is sometimes mentioned in the news. Which of the following best explains its principle?
(a)

It uses immune cells trained or modified to recognize and destroy cancer or infected cells.

(b)

It delivers synthetic hormones to activate the thyroid and lymph nodes to boost immunity.

(c)

It suppresses the body’s immune cells to prevent excessive antibody production.

(d)

It replaces defective bone marrow cells with donor stem cells to regenerate immunity.

Explanation

Core idea: T-cell therapy harnesses the body’s own immune T cells — either collected and expanded, or genetically modified — to recognize and kill cancer cells or virus-infected cells.

Why others are wrong: Options (b), (c), and (d) describe unrelated mechanisms such as endocrine stimulation, immunosuppression, or bone marrow transplantation.

Answer: (a)
Q9. Which one of the following situations would most likely lead to increased risk of autoimmune diseases?
(a)

The body produces excessive Regulatory T cells (Tregs).

(b)

The activity of Regulatory T cells is suppressed or their number declines.

(c)

The FOXP3 gene is overexpressed in T cells.

(d)

Checkpoint inhibitors block PD-1 and CTLA-4 receptors on T cells.

Explanation

Regulatory T cells (Tregs) prevent the immune system from attacking the body’s own tissues.

When Treg activity decreases (or the FOXP3 gene is defective), self-tolerance breaks down, causing autoimmune disease.

(a) and (c) would enhance tolerance, not reduce it.

(d) Checkpoint blockade boosts immune attack (used in cancer therapy), not necessarily a direct cause of autoimmune disorders — though mild immune side effects may occur.

Answer: (b)
Q10. Which one of the following regions, often referred to as the “Amazon of the Seas,” is associated with a recent initiative to establish a coral larvae cryobank for preserving reef biodiversity?
(a)

Great Barrier Reef

(b)

Coral Triangle

(c)

Red Sea Coral Belt

(d)

Caribbean Reef System

Explanation

The Philippines has launched the world’s first coral larvae cryobank as part of a regional effort within the Coral Triangle, a 5.7 million sq. km marine zone spanning Indonesia, Malaysia, Papua New Guinea, the Philippines, Solomon Islands, and Timor-Leste.

It is known as the “Amazon of the Seas” for hosting the planet’s highest coral and reef fish diversity.

Answer: (b) Coral Triangle
The Coral Triangle — The “Amazon of the Seas”

The Coral Triangle is a vast marine region in the western Pacific Ocean spanning Indonesia, Malaysia, Papua New Guinea, the Philippines, Solomon Islands, and Timor-Leste. Covering around 5.7 million sq km, it is known as the most biodiverse marine area on Earth.

Biodiversity Significance:
  • Contains about 76% of the world’s coral species and 3,000+ species of reef fish.
  • Serves as a nursery ground for numerous marine species and supports vital oceanic food webs.
Human and Ecological Importance:
  • Provides livelihoods and food security for nearly 120 million coastal residents.
  • Contributes to climate regulation and storm protection through coral and mangrove ecosystems.
Major Threats:
  • Unsustainable fishing and coastal pollution
  • Coral bleaching due to climate change
  • Habitat loss and fossil fuel exploration
Conclusion: Nicknamed the “Amazon of the Seas,” the Coral Triangle’s unmatched marine biodiversity mirrors the ecological importance of the Amazon rainforest on land.