1. With reference to land subsidence, consider the following statements:
1. It refers to the gradual sinking of the Earth’s surface.
2. Over-extraction of groundwater is one of its major causes.
3. It occurs only due to tectonic activity.
Which of the statements given above is/are correct?
(a) 1 and 2 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (a)1 and 2 only
Explanation:
Land subsidence is defined as the gradual settling or sudden sinking of the Earth’s surface. This occurs when the subsurface materials (soil, rock, or water) move or are removed, leaving a void or a compressed layer that cannot support the weight of the ground above it.Hence Statement 1 is correct.
The over-extraction of groundwater is the most common cause of land subsidence globally. When large amounts of water are pumped from underground aquifers, the pore pressure in the soil decreases. This leads to the compaction of fine-grained sediments (like clay), causing the land to sink. Other human-induced causes include mining, oil and gas extraction, and heavy infrastructure development.Hence Statement 2 is correct.
While tectonic activity (such as earthquakes or faulting) can indeed cause land subsidence, it is not the only cause. As mentioned above, it occurs due to a variety of anthropogenic (human-led) factors and other natural processes like the dissolution of limestone (karst topography) or the thawing of permafrost.Hence Statement 3 is incorrect.
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| PYQ REFERENCE:UPSC 2021 Q Which of the following can be the causes of land subsidence? 1. Extraction of natural gas 2. Tectonic activities 3. Thawing of permafrost 4. Massive urban infrastructure weight Select the correct answer using the code given below: (a) 1, 2 and 4 only (b) 2 and 3 only (c) 1 and 4 only (d) 1, 2, 3 and 4 |
2. Consider the following statements about aquifers:
1. An aquifer is an underground layer that stores groundwater.
2. Over-extraction of groundwater can lead to compaction of aquifers.
3. Aquifer depletion has no impact on surface infrastructure.
Which of the statements given above is/are correct?
(a) 1 and 2 only
(b) 1 only
(c) 2 and 3 only
(d) 1, 2 and 3
Answer: (a)1 and 2 only
Explanation:
An aquifer is a body of porous rock or sediment saturated with groundwater. It acts as a natural underground reservoir. Groundwater enters an aquifer as precipitation seeps through the soil and is stored in the spaces between particles or in cracks in the rocks.Hence Statement 1 is correct:
This is a critical geological consequence of over-extraction. When water is pumped out of an aquifer faster than it can be recharged, the fluid pressure that previously helped support the weight of the overlying soil and rock (overburden) decreases. This causes the sediment layers to compress and pack more tightly together—a process known as compaction. Once an aquifer is severely compacted, its ability to store water in the future is often permanently reduced.Hence Statement 2 is correct:
Aquifer depletion has a massive impact on surface infrastructure. As the aquifer compacts, the land surface above it begins to sink (land subsidence). This can result in:
- Structural damage: Cracking of building foundations, roads, and bridges.
- Utility disruption: Breaking of underground water and sewer pipes or telecommunication cables.
- Drainage issues: Changes in the slope of the land can disrupt natural canal flows and increase the risk of flooding in urban areas.Hence Statement 3 is incorrect:
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| PYQ REFERENCE:UPSC 2023 Q. Consider the following statements: Statement-I: According to the United Nations’ World Water Development Report, 2022, India extracts more than a quarter of the world’s groundwater withdrawal each year. Statement-II: India needs to extract more than a quarter of the world’s groundwater each year to satisfy the drinking water and sanitation needs of almost 18% of the world’s population living in its territory. Which one of the following is correct in respect of the above statements? (a) Both Statement-I and Statement-II are correct and Statement-II is the correct explanation for Statement-I. (b) Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-I. (c) Statement-I is correct but Statement-II is incorrect. (d) Statement-I is incorrect but Statement-II is correct. |
3. Which of the following can be monitored using satellite-based Earth observation systems like NISAR?
1. Land subsidence
2. Glacier movement
3. Fault line activity
4. Urban expansion
Select the correct answer using the code below:
(a) 1 and 2 only
(b) 1, 2 and 3 only
(c) 2, 3 and 4 only
(d) 1, 2, 3 and 4
Answer: (d)1,2,3 and 4
Explanation:
The NISAR (NASA-ISRO Synthetic Aperture Radar) mission is designed specifically to observe and measure some of the planet’s most complex natural processes. Because it uses Synthetic Aperture Radar (SAR), it can “see” through clouds and darkness, providing data regardless of weather conditions.
- 1. Land Subsidence:
NISAR uses a technique called Interferometric SAR (InSAR). By comparing radar signals from two different points in time, it can detect surface deformation (sinking or rising) with millimeter-scale precision. This is vital for monitoring sinking cities and groundwater depletion. - 2. Glacier Movement:
SAR is highly effective at tracking the velocity of ice sheets and glaciers. It helps scientists monitor the rate of ice loss and the movement of glaciers in the Himalayas and polar regions, which is crucial for climate change studies. - 3. Fault Line Activity:
NISAR can map ground displacement caused by tectonic stress. It monitors crustal deformation along fault lines before and after earthquakes, providing insights into seismic risks and help in mapping tectonic plate boundaries. - 4. Urban Expansion:
The mission tracks changes in land use and land cover. Its high-resolution imaging allows for the monitoring of infrastructure growth, urban sprawl, and the environmental impact of rapid urbanization.
Quick Facts: NISAR for UPSC Prelims
| Feature | Details |
| Joint Venture | NASA (USA) and ISRO (India). |
| Frequencies | First satellite to use dual frequencies: L-band (NASA) and S-band (ISRO). |
| Orbit | Low Earth Orbit (LEO) – Sun-synchronous. |
| Primary Goal | Global observation of “Earth in Change”—biomass, natural hazards, and ice sheet dynamics. |
| Data Policy | It provides free and open data, which is a significant resource for global research and disaster management. |
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| PYQ REFERENCE:UPSC 2019 Q. For the measurement/estimation of which of the following are satellite images/remote sensing data used? 1. Chlorophyll content in the vegetation of a specific location 2. Greenhouse gas emissions from rice paddies of a specific location 3. Land surface temperatures of a specific location Select the correct answer using the code given below: (a) 1 only (b) 2 and 3 only (c) 3 only (d) 1, 2 and 3 |
4. A “biosimilar” drug refers to:
(a) An exact chemical copy of a generic drug
(b) A cheaper version of a synthetic drug
(c) A nearly identical copy of a biologic drug
(d) A drug with a completely new mechanism
Answer: (c)A nearly identical copy of a biologic drug
Explanation:
While they might sound like standard generic drugs, biosimilars are a bit more complex due to how they are made. Here is a breakdown of why (c) is the right choice and how it differs from the other options:
1. What is a Biologic?
Unlike traditional drugs (like aspirin), which are synthesized through chemical processes, biologics are derived from living organisms (such as bacteria, yeast, or animal cells). Because living systems are inherently variable, these drugs are massive, complex molecules.
2. Why “Nearly Identical”?
Because biologics are grown rather than “mixed,” it is impossible to create an exact structural copy.
- Generics (Option A): These are exact chemical copies of “small-molecule” drugs. Think of it like a simple LEGO set; you can replicate it perfectly every time.
- Biosimilars (Option C): These are like trying to grow a second oak tree that is “highly similar” to the first. They have the same therapeutic effect and safety profile, but the microscopic sugar chains or folding might vary slightly.
3. Comparison Table
| Feature | Generic Drug | Biosimilar Drug |
| Source | Chemical synthesis | Living cells/organisms |
| Size | Small, simple molecules | Large, complex molecules |
| Structure | Identical to brand name | Highly similar (not identical) |
| Approval | Must show bioequivalence | Must show no clinical difference |
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| PYQ REFERENCE:UPSC 2018 Q. Which of the following statements is/are correct regarding the Pradhan Mantri Bhartiya Janaushadhi Pariyojana? 1. Affordable medicines including biosimilars are made available under this scheme. 2. The scheme is implemented by the Department of Pharmaceuticals. (a) 1 and 2 both (b) 1 only (c) 2 only (d) Neither |
5. Which of the following best distinguishes the Model Code of Conduct (MCC) from the Representation of the People Act (RPA), 1951?
(a) MCC is legally binding, while RPA is advisory
(b) MCC is flexible and open-textured, while RPA is statutory and specific
(c) MCC applies only to candidates, while RPA applies only to parties
(d) MCC is enforced by courts, while RPA is enforced by the Election Commission
Answer:(b) MCC is flexible and open-textured, while RPA is statutory and specific
Explanation:
The relationship between the Model Code of Conduct (MCC) and the Representation of the People Act (RPA), 1951, is a cornerstone of Indian electoral governance. The primary difference lies in their legal nature and rigidity.
Key Distinctions
| Feature | Model Code of Conduct (MCC) | Representation of the People Act, 1951 |
| Legal Status | Non-Statutory. It is a set of guidelines evolved through consensus among political parties. | Statutory. It is a law passed by Parliament. |
| Enforceability | It does not have statutory backing and is not legally binding in a court of law. | It is legally binding and enforceable through the judicial system. |
| Flexibility | Open-textured. It allows the Election Commission (ECI) to interpret “fair play” based on the spirit of the guidelines. | Specific. It contains rigid definitions of corrupt practices and electoral offenses. |
| Punishment | Enforcement relies on moral sanction, “naming and shaming,” or temporary bans on campaigning. | Violations can lead to imprisonment, fines, or disqualification of the candidate. |
Why the other options are incorrect:
- (a) is reversed: The RPA is legally binding (statutory), while the MCC is technically advisory/consensus-based (though the ECI uses its powers under Article 324 to ensure compliance).
- (c) is incorrect: Both the MCC and the RPA apply to both candidates and political parties. For instance, Section 123 of the RPA deals with “corrupt practices” by candidates, while the MCC has specific chapters for Party manifestos and conduct.
- (d) is incorrect: While the ECI enforces both, the RPA is ultimately a law of the land triable in courts (High Courts for election petitions). The MCC is almost exclusively the domain of the ECI, as courts generally do not interfere with its enforcement during the “election process.”
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6. With reference to the Model Code of Conduct (MCC), consider the following statements:
1. It was first introduced by the Election Commission of India in 1968.
2. It becomes operative from the announcement of the election schedule.
3. It has statutory backing under the Representation of the People Act, 1951.
Which of the statements given above is/are correct?
(a) 2 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
Answer: (a) 2 only
Explanation:
The Model Code of Conduct (MCC) was not introduced by the ECI in 1968. It actually traces its origins to the 1960 Kerala Assembly elections, where the state administration prepared a draft code for political parties. The ECI first circulated this code to all recognized political parties during the 1962 Lok Sabha elections. A more comprehensive version was issued later, but 1968 is not the starting point.Hence Statement 1 is incorrect.
The MCC becomes operative the moment the Election Commission of India (ECI) announces the election schedule via a press conference. It remains in force until the results are declared. This was a point of contention until the Supreme Court (in the Harbans Singh Jalal case) upheld that the “announcement” date is the trigger point, not the “notification” date.Hence Statement 2 is correct.
The MCC does not have statutory backing. It is a set of guidelines evolved through consensus among political parties. While there have been recommendations (such as from the Parliamentary Standing Committee on Personnel, Public Grievances, Law and Justice in 2013) to give it legal backing under the RPA 1951, the ECI has opposed this. The ECI argues that making it statutory would subject every violation to slow-moving judicial proceedings, making it impossible to take the swift action required during an election cycle.Hence Statement 3 is incorrect.
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7. Which of the following are provided for in the Representation of the People Act, 1951?
1. Registration of political parties.
2. Qualifications and disqualifications for membership of Houses.
3. Preparation of electoral rolls.
4. The actual conduct of elections and bye-elections.
Select the correct answer using the codes given below:
(a) 1, 2 and 4 only
(b) 2, 3 and 4 only
(c) 1 and 3 only
(d) 1, 2, 3 and 4
Answer: (a)1, 2 and 4 only
Explanation:
To answer this correctly, you must distinguish between the two primary pillars of Indian election law: the Representation of the People Act (RPA), 1950 and the Representation of the People Act (RPA), 1951.
Why Statement 3 is Incorrect
Preparation of electoral rolls is provided for under the RPA 1950. Think of the 1950 Act as the “pre-election” framework—it deals with the administrative setup before a candidate even enters the picture. It covers:
- Delimitation of constituencies.
- Allocation of seats in the legislatures.
- Qualifications of voters (not candidates).
- The preparation and revision of electoral rolls.
Why Statements 1, 2, and 4 are Correct
The RPA 1951 is the “operational” framework—it deals with the actual process of contesting and conducting an election. Its provisions include:
- Registration of Political Parties: Section 29A of the 1951 Act provides the mechanism for a group to register as a political party with the Election Commission.
- Qualifications and Disqualifications: While the Constitution provides basic criteria, the 1951 Act specifies detailed grounds for disqualification (e.g., conviction for certain offenses, failure to lodge election expenses, or corrupt practices).
- Conduct of Elections: It lays out the procedure for nominations, the poll process, the counting of votes, and the declaration of results.
- Bye-elections: It provides the legal basis for filling casual vacancies in the Houses of Parliament and State Legislatures.
- Corrupt Practices: It defines what constitutes a corrupt practice (like bribery or undue influence) and provides the mechanism for challenging an election via “Election Petitions.”
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8. Consider the following statements regarding grazing rights under FRA:
1. FRA recognises grazing rights of forest dwellers.
2. These rights apply even in protected areas like national parks and tiger reserves.
3. State laws can override FRA in matters of grazing.
Which of the statements given above is/are correct?
(a) 1 and 2 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer:(a) 1 and 2 only
Explanation:
The Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006 (FRA) is a critical piece of legislation that seeks to undo “historical injustice” by recognizing the rights of forest-dwelling communities.
- Under Section 3(1)(d) of the FRA, the Act explicitly recognizes community rights such as grazing (both settled and transhumant) and traditional seasonal resource access of nomadic or pastoralist communities.Hence Statement 1 is correct.
- The FRA applies to all “forest land,” which includes Protected Areas like National Parks, Wildlife Sanctuaries, and Tiger Reserves. While these areas have higher levels of protection, the FRA mandates that forest rights must be recognized there first. Any relocation or restriction of rights in “Critical Wildlife Habitats” can only happen after the rights have been fully recognized and settled, and after it is scientifically established that the presence of holders will cause irreversible damage.Hence Statement 2 is correct.
- The FRA is a Central Act that overrides conflicting state laws. While state governments are responsible for its implementation, they cannot bypass or override the provisions of the FRA regarding the recognition of rights. In fact, Section 13 of the FRA states that the provisions of this Act shall be in addition to and not in derogation of any other law for the time being in force—meaning it acts as a protective shield for forest dwellers against restrictive state forest laws.Hence Statement 3 is incorrect.
IN NEWS: What does the latest ruling mean for the Forest Rights Act?
| PYQ REFERENCE:UPSC 2021 Q. At the national level, which ministry is the nodal agency to ensure effective implementation of the Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006? (a) Ministry of Environment, Forest and Climate Change (b) Ministry of Panchayati Raj (c) Ministry of Rural Development (d) Ministry of Tribal Affairs |
9. Mexico is bordered by which of the following water bodies?
1. Gulf of Mexico
2. Caribbean Sea
3. Pacific Ocean
4. Atlantic Ocean
Select the correct answer using the code below:
(a) 1, 2 and 3 only
(b) 1 and 3 only
(c) 2 and 4 only
(d) 1, 2, 3 and 4
Answer: (a)1,2 and 3 only
Explanation:
1. The Western Coast
- Pacific Ocean: Mexico has an extensive western coastline along the Pacific Ocean.
- Gulf of California: This is a marginal sea of the Pacific Ocean, located between the Baja California Peninsula and the Mexican mainland.
2. The Eastern Coast
- Gulf of Mexico: This is the primary water body to the east, bordered by several Mexican states including Tamaulipas, Veracruz, and Tabasco.
- Caribbean Sea: Mexico borders the Caribbean Sea at the southeastern tip of the Yucatán Peninsula (specifically the state of Quintana Roo). This area is famous for the Mesoamerican Barrier Reef.
3. Why the “Atlantic Ocean” is Incorrect
While the Gulf of Mexico and the Caribbean Sea are technically marginal seas of the Atlantic Ocean, in geographical and cartographic terms, Mexico does not have a direct “Atlantic Ocean” coastline. The Atlantic coastline of North America is generally considered to begin north of the Florida Straits or east of the Greater Antilles.
Quick Geographical Facts for Revision:
- Northern Border: United States.
- Southern Borders: Guatemala and Belize.
- Key Peninsulae: Baja California (West) and Yucatán (East).
- Isthmus of Tehuantepec: The narrowest point between the Gulf of Mexico and the Pacific Ocean.
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10. With reference to ‘Ocean Mean Temperature’ (OMT), which of the following statements is/are correct?
1. OMT is measured up to a depth of 26°C isotherm which is 129 meters in the south-western Indian Ocean during January — March.
2. OMT collected during January — March can be used in assessing whether the amount of rainfall in monsoon will be less or more than a certain long-term mean.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer: (b) 2 only
Explanation:
- While the 26°C isotherm is used, its depth varies significantly. In the south-western Indian Ocean, it usually ranges between 50–100 meters, not a constant 129 meters. Hence Statement 1 is incorrect.
- OMT is a better predictor of the Indian Summer Monsoon than Sea Surface Temperature (SST) because it measures the heat content of a larger volume of water, offering more stability and accuracy in forecasting. Hence Statement 2 is correct.