UGC NET Questions (Paper – 1)

Noise pollution refers to unwanted or harmful sound in the environment. Sound intensity is measured on a logarithmic scale called the decibel scale. Environmental and occupational standards specify safe limits in decibels for different settings. Therefore, decibel (dB) is the correct unit used for noise levels.

Option A:
Option A is incorrect because parts per million are used for concentrations of gases or solutes, not for sound. Air pollutants like SO₂ or NO₂ may be reported in ppm.

Option B:
Option B is correct as decibel is the standard unit for sound intensity. It allows comparison of noise levels from different sources on a common scale.

Option C:
Option C is incorrect since hertz measures frequency, not loudness. Frequency describes pitch, while decibels indicate intensity.

Option D:
Option D is incorrect because lumen is a unit of luminous flux used in lighting, not sound. It is relevant to visual, not auditory, pollution.

Statements A, B, D, E and F are all correct and together explain which gases are important, how the enhanced greenhouse effect works and how radiation is trapped. Carbon dioxide is the main long-lived anthropogenic gas, methane is more potent per unit mass, water vapour is a feedback gas and greenhouse gases absorb outgoing longwave radiation. Statement C is false because nitrous oxide and many fluorinated gases are well-known greenhouse gases with significant warming effects. Therefore, the combination that includes A, B, D, E and F only is correct.

Option A:
Option A is incorrect because it leaves out F and therefore fails to mention the basic physical mechanism of longwave absorption by greenhouse gases. Without F, the explanation of how warming actually occurs remains incomplete.

Option B:
Option B is correct as it lists all the true statements and excludes only C, which denies the greenhouse role of nitrous oxide and fluorinated gases. It provides a conceptually coherent description of greenhouse gases and the enhanced greenhouse effect.

Option C:
Option C is incorrect since it includes C, which is demonstrably wrong, and omits B, thereby losing the point about methane’s higher warming potential. This mixture of errors and omissions makes it unsuitable as the correct answer.

Option D:
Option D is incorrect because it omits A, ignoring the central role of carbon dioxide, while also excluding A’s emphasis on the primary anthropogenic driver. It also contains only a subset of true statements and thus does not fully characterise greenhouse gas behaviour.

Composting uses microorganisms to break down organic waste such as food scraps, garden trimmings and farm residues. Under controlled moisture, temperature and aeration, this biological process converts waste into a stable, humus-like product that can be applied to soil as manure. It reduces the amount of biodegradable material going to landfills and recycles nutrients back into the ecosystem. Therefore, describing composting as controlled biological decomposition of organic waste is accurate.

Option A:
Option A is incorrect because shredding plastics is a physical pre-treatment for recycling, not a biological transformation. Plastics do not decompose in normal composting systems and require different handling methods.

Option B:
Option B is correct as it specifies both the biological nature of the process and the beneficial end product. Properly managed composting can also reduce pathogens and odours, making it a sustainable option for organic waste management.

Option C:
Option C is incorrect since incineration involves burning waste to reduce volume and possibly recover energy. While it can treat mixed waste, it does not produce manure and has different environmental implications, including air emissions.

Option D:
Option D is incorrect because landfilling hazardous waste is a containment strategy for dangerous materials. Composting, in contrast, is intended for biodegradable organic matter and is not an appropriate method for hazardous chemicals.

Statements A, B, C, D and F are correct and collectively describe ecological, functional, cultural, climate and economic dimensions of biodiversity. Biodiversity supports key services, loss harms livelihoods, cultural meanings are important, conservation aids mitigation and adaptation, and payment schemes reward service provision. Statement E is wrong because biodiversity clearly remains essential for food, health, materials and cultural identity even in modern societies. Therefore, the combination that includes all true statements and excludes E is correct.

Option A:
Option A is incorrect as it omits F, which correctly notes the role of payment for ecosystem services in incentivising conservation. Without F, the answer misses an important policy mechanism linked to ecosystem services.

Option B:
Option B is incorrect because it leaves out C while including F. Cultural services are a standard category in ecosystem service frameworks, so excluding C gives an incomplete view of biodiversity’s contributions.

Option C:
Option C is incorrect as it includes E, a statement that denies the relevance of biodiversity to modern human well-being. Since E is clearly false, this combination mixes correct and incorrect statements.

Option D:
Option D is correct because it aggregates all the accurate statements—ecological, livelihood, cultural, climate and economic—and excludes only the claim that biodiversity has no relevance. It thus reflects the integrated role of biodiversity in people, development and environment.

Statements A, B, D and F are correct, showing that environmental factors interact with other drivers of migration, that people sometimes move as an adaptation strategy, that policies must consider livelihoods and rights and that improved data are needed. Statement C is wrong because environmental migration can be temporary, seasonal or permanent, and E is wrong because internal movements are an important part of environment–migration linkages. Thus, the option that includes A, B, D and F and excludes C and E is correct.

Option A:
Option A is incorrect because it omits D and F, ignoring the need for protective and livelihood-sensitive policies and for better evidence to guide them. While it captures environmental drivers and adaptation, it does not reflect the policy and research dimensions fully.

Option B:
Option B is correct as it brings together the most widely accepted points about environmental migration while rejecting overly rigid or dismissive views. It recognises complexity, adaptation, policy responsibilities and knowledge gaps, which matches the conceptual treatment in this unit.

Option C:
Option C is incorrect since it includes C, which wrongly states that all movement is permanent, even though migration responses to environmental change often include circular and seasonal patterns. Including C means the option mixes true and false statements.

Option D:
Option D is incorrect because it accepts E, which claims internal migration is irrelevant, and excludes A. Internal movements are central to environment–migration debates, so this combination seriously misrepresents the field.

Statements A, C and D are correct because they describe widely accepted principles and practices of sustainable agriculture. Diversification, conservation tillage, organic methods and a balance between environmental quality and farm income are central goals. Statement B is incorrect as excessive reliance on chemical inputs is characteristic of unsustainable, input-intensive agriculture. Therefore, the combination that includes A, C and D only is the correct answer.

Option A:
Option A is incorrect because it includes A and C but omits D. While diversification and conservation tillage are valid aspects, leaving out the goal of maintaining soil fertility and environmental quality along with profitability makes the set incomplete. A comprehensive answer must recognise this objective.

Option B:
Option B is correct because it captures the full cluster of correct statements while excluding the misleading one. It reflects that sustainable agriculture integrates diversified systems, ecological practices and long-term soil and environmental health with economic viability. By omitting statement B, it avoids endorsing overuse of chemicals.

Option C:
Option C is incorrect because it adds statement B to an otherwise correct set. Statement B falsely portrays heavy use of chemical fertilisers and pesticides as a feature of sustainability, which contradicts concerns about soil degradation, water pollution and biodiversity loss. The presence of this false statement invalidates the option.

Option D:
Option D is incorrect because it claims that B, C and D are correct, again treating B as acceptable. Although C and D are right, including B, which promotes unsustainable input dependence, makes the combination inconsistent with the concept of sustainable agriculture.

Impact prediction is the stage of EIA where analysts estimate the type,extent and significance of environmental changes likely to result from a proposed project. It uses baseline data,models and expert judgement to forecast impacts. These predictions guide the development of mitigation measures and inform decision makers. Therefore the description in the question clearly refers to impact prediction.

Option A:
Screening is the initial step to decide whether a project requires a full EIA or not. It does not involve detailed estimation of environmental changes. Hence it does not match the stage described in the stem.

Option B:
Scoping identifies the key issues,impacts and alternatives that need detailed study in the EIA. It determines the boundaries and focus of the assessment. While important,it precedes the actual quantification and evaluation of impacts.

Option C:
Public hearing is a participatory step where affected communities and stakeholders express their views on the proposed project and its impacts. It provides qualitative input but is not the technical phase of estimating magnitude and significance. Therefore it is not the correct answer.

Option D:
Impact prediction produces scenarios of how air,water,soil,flora,fauna and socio economic conditions may change if a project proceeds. These results are essential for deciding whether to approve,modify or reject the project. This aligns exactly with the description given in the question.

Statements A, B, C, E and F are correct on hearing loss, non-auditory effects, silence zones, transport noise and control measures. Statement D is false because chronic noise exposure is linked with cardiovascular outcomes such as hypertension. Hence, the correct combination is A, B, C, E and F only.

Option A:
Option A is correct because it includes all true statements and excludes D, which wrongly denies cardiovascular impacts.

Option B:
Option B is incorrect because it omits F, missing key mitigation strategies like barriers, traffic management and building design.

Option C:
Option C is incorrect because it includes D (false) and omits A (true).

Option D:
Option D is incorrect because it omits B, ignoring stress and sleep disturbance as major health effects.

Effective climate strategies combine actions to limit emissions with efforts to adapt to inevitable impacts. Improving efficiency reduces energy demand, while scaling up renewables decarbonises supply. At the same time, investing in resilient infrastructure and mainstreaming adaptation into agriculture, water, health and urban planning helps societies cope with changing climate risks. Together these measures reflect an integrated approach consistent with international guidance on climate-resilient development.

Option A:
Option A is incorrect because subsidising fossil fuels and abandoning renewable targets lock economies into high-carbon pathways and increase vulnerability to future policy and market shifts.

Option B:
Option B is correct because it combines mitigation and adaptation instruments in a coherent framework, aligning with many national climate action plans and global recommendations.

Option C:
Option C is incorrect since focusing only on forests, while valuable, leaves out major emitting sectors like energy, industry and transport and neglects adaptation needs in vulnerable communities.

Option D:
Option D is incorrect because delaying domestic action until others move risks higher future costs and undermines collective efforts to stabilise the climate.

Statements A, B, C, E and F are correct and illustrate flood mitigation, groundwater recharge, biodiversity support, nature-based solutions and common pressures like encroachment/dumping. Statement D is wrong because wetland conversion typically worsens flooding and degrades water quality. Therefore, the correct answer is A, B, C, E and F only.

Option A:
Option A is correct because it includes all true statements and excludes D, which falsely claims wetland loss has no effects.

Option B:
Option B is incorrect because it omits F, missing a major set of real-world pressures on urban wetlands.

Option C:
Option C is incorrect because it includes D (false).

Option D:
Option D is incorrect because it omits B, underrepresenting key eco-hydrological services like groundwater recharge/baseflow support.

Sex ratio measures the balance between females and males in a population,often expressed as females per thousand males. It helps reveal gender related patterns such as discrimination or selective survival. The stem reproduces this definition almost exactly,so sex ratio is the correct term. Therefore Option B is appropriate.

Option A:
Age ratio compares different age groups and relates to age structure,not female-to-male composition.

Option B:
Sex ratio is the standard demographic indicator for females per thousand males and is widely used to assess gender balance in populations.

Option C:
Dependency ratio compares dependants to working age people,not females to males.

Option D:
Literacy ratio is not the standard term for female-to-male counts and does not match the stem’s definition.

Statements A, B, C, D and F are correct: walking/cycling are NMT; infrastructure encourages use; NMT has no tailpipe emissions; it reduces congestion and improves air/health; and integration with public transport improves mobility. Statement E is false because NMT planning is important in cities across all income levels. Therefore, the correct set is A, B, C, D and F only.

Option A:
Option A is incorrect because it omits F, missing the important role of integrating NMT with public transport for a complete mobility system.

Option B:
Option B is correct because it includes all true statements and excludes only E, which wrongly restricts NMT relevance to low-income countries.

Option C:
Option C is incorrect because it includes E (false).

Option D:
Option D is incorrect because it omits B and A, so it underrepresents both infrastructure and the definition/examples of NMT.

Statement A is wrong because in practice indigenous territories are often directly affected by mining, logging, dams and other large projects. Statements B, C, D, E and F are correct: indigenous communities hold rich ecological knowledge, international standards recognise their rights, free prior and informed consent is a key safeguard, ignoring rights can fuel conflicts and recognised land rights can support conservation. Thus, the only wrong statement is A.

Option A:
Option A is correct as it identifies A alone as the wrong statement and leaves the remaining statements recognised as true. It captures the reality that indigenous territories face intense external pressures despite having internationally affirmed rights.

Option B:
Option B is incorrect since it treats both A and B as wrong, even though B is a valid description of indigenous ecological knowledge. Misclassifying B contradicts extensive documentation of community-based knowledge systems.

Option C:
Option C is incorrect because it labels A and F as wrong together. F correctly notes that recognising land rights can promote better forest outcomes, so including it with A undermines the empirical evidence on rights-based conservation.

Option D:
Option D is incorrect as it groups A with B and C as wrong, even though both B and C are accurate statements about knowledge and rights frameworks. This option therefore fails to distinguish between incorrect and correct claims.

Wind energy harnesses the kinetic energy of moving air using turbines connected to generators. During operation, this process does not involve combustion and therefore does not release carbon dioxide, sulphur dioxide, particulates or other typical power-plant pollutants. While there are impacts associated with manufacturing and installation, the operational emissions are very low compared with coal-based thermal power. Hence, the absence of direct greenhouse gas and air pollutant emissions during operation is a key environmental advantage.

Option A:
Option A is correct because it highlights the major environmental benefit of wind power, namely low operational emissions. This makes wind a critical component of strategies aiming to decarbonise electricity systems and reduce local air pollution.

Option B:
Option B is incorrect since wind farms do require land or offshore space for turbine placement and access roads. Land-use planning is an important consideration in wind-energy development.

Option C:
Option C is incorrect because wind turbines do not consume coal; they replace the need for coal-based electricity generation. Suggesting they use coal misunderstands the technology.

Option D:
Option D is incorrect as wind can blow at any time of day depending on local weather patterns. Wind availability is variable, but it is not restricted to nighttime.

Statements A and B are correct because active transport improves health and transport-related air pollution is linked with respiratory and cardiovascular problems. Statement C is wrong since road design, crossings and traffic calming are crucial for pedestrian and cyclist safety. Statement D is also false as health impact assessments are increasingly used in major transport projects. Therefore, the combination A and B only is the correct answer.

Option A:
Option A is correct since it captures the two accurate statements while excluding C and D, both of which deny established links between planning, safety and health assessments. It reflects the role of both physical activity promotion and pollution control in transport policy.

Option B:
Option B is incorrect because it adds C to A and B, thereby accepting the claim that road design has no link with safety. This contradicts road safety science and practice, so the option cannot be accepted.

Option C:
Option C is incorrect as it groups B, C and D. While B is true, C and D are false, so this combination mixes correct and incorrect statements and fails to represent the set of correct statements.

Option D:
Option D is incorrect because it assumes all four statements are correct, thereby endorsing C and D. Since both are wrong, the entire combination becomes invalid.