CPCB Recruitment 2025 Paper Posted inQuiz CPCB Recruitment 2025: Practice Test Posted by kanwar June 18, 2025No Comments 113 CPCB 2025 Examination 25 Basics Questions. Helpfull for Sci-B, SSA 1 / 25 1. The AQI category for values 101–150 is: A. Good B. Moderate C. Unhealthy for Sensitive Groups D. Unhealthy 2 / 25 2. Which ion exchange phenomenon is responsible for the reduced bioavailability of heavy metals in soils with high CEC? A. Ligand exchange B. Inner-sphere complexation C. Competitive cation exchange D. Anion exclusion 3 / 25 3. A country achieving “net negative emissions” must: A. Eliminate all fossil fuel use B. Reduce emissions by 50% below 1990 levels C. Remove more CO₂ than it emits annually D. Rely exclusively on Renewable energy & Eliminate all fossil fuel use 4 / 25 4. Which of the following is a biodiversity hotspot in India? A. Thar Desert B. Western Ghats C. Gangetic Plains D. Aravalli Range 5 / 25 5. In the Winkler DO method, why is manganese sulfate (MnSO₄) added before alkali-iodide-azide? A. To oxidize organic matter B. To neutralize acidic conditions C. To precipitate dissolved oxygen as MnO₂ D. To catalyze iodine liberation 6 / 25 6. Which greenhouse gas has the highest Global Warming Potential (GWP) over 20 years? A. Carbon dioxide (CO₂) B. Methane (CH₄) C. Nitrous oxide (N₂O) D. Sulfur hexafluoride (SF₆) 7 / 25 7. The “Wildlife Protection Act” in India was enacted in which year? A. 1972 B. 1981 C. 1986 D. 1991 8 / 25 8. What does the term “keystone species” refer to? A. A species with the largest population B. A species critical for ecosystem stability C. A recently discovered species D. An invasive (Non Native) species 9 / 25 9. Under the Paris Agreement, what is India’s “NDC” target for reducing emission intensity by 2030? A. 20-25% below 2005 levels B. 33-35% below 2005 levels C. 40-45% below 2005 levels D. 50-55% below 2005 levels 10 / 25 10. What is the primary pollutant measured by the Air Quality Index (AQI) that dominates urban smog? A. Ozone (O₃) B. Carbon monoxide (CO) C. Particulate Matter (PM₂.₅) D. Sulfur dioxide (SO₂) 11 / 25 11. The “Polluter Pays Principle” was legally enforced in India through which landmark case? A. MC Mehta vs. Union of India (Ganga Pollution Case) B. Vellore Citizens Welfare Forum vs. Union of India C. Oleum Gas Leak Case D. Taj Trapezium Case 12 / 25 12. A proposed highway through a tiger reserve requires what level of EIA as per Indian laws? A. Category A (MoEFCC appraisal) B. Category B1 (State EAC appraisal) C. Exempted if width <100m D. Requires only public hearing 13 / 25 13. What does the “3Rs” principle in waste management stand for? A. Reduce, Reuse, Recycle B. Repair, Recover, Refine C. Remove, Replace, Restore D. Regulate, Report, Reclaim 14 / 25 14. Which spectral index would best detect algal blooms in a lake using satellite data? A. NDVI (Normalized Difference Vegetation Index) B. NDWI (Normalized Difference Water Index) C. MNDWI (Modified NDWI) D. FAI (Floating Algae Index) 15 / 25 15. Why is fluorescein diacetate (FDA) hydrolysis used in soil microbiology? A. To quantify fungal biomass B. To measure total microbial activity C. To detect nitrate-reducing bacteria D. To isolate antibiotic-resistant strains 16 / 25 16. The photochemical smog reaction that produces peroxyacetyl nitrate (PAN) primarily involves which two pollutants? A. NO₂ + CO B. VOCs + NOx C. SO₂ + O₃ D. PM₂.₅ + CO₂ 17 / 25 17. Which virus is frequently detected in sewage due to fecal contamination? A. Influenza virus B. Norovirus C. Dengue virus D. Ebola virus 18 / 25 18. Which agency is responsible for approving Environmental Impact Assessments (EIAs) for national projects in India? A. State Pollution Control Board (SPCB) B. Ministry of Environment, Forest and Climate Change (MoEFCC) C. Central Pollution Control Board (CPCB) D. National Green Tribunal (NGT) 19 / 25 19. The EC₅₀ value in ecotoxicology refers to: Options: A. Exposure concentration causing 50% mortality B. Dose accumulating in 50% of organisms C. Effective concentration for 50% population response D. Time required for 50% chemical degradation 20 / 25 20. Which titration method is used to determine the hardness of water? A. Mohr’s method B. Winkler method C. EDTA method D. Kjeldahl method 21 / 25 21. The Recycled Plastics Usage Rules____________ ? A. 1998 B. 2000 C. 2001 D. 2002 22 / 25 22. What is the main cause of soil salinization in agricultural fields? A. Excessive use of pesticides B. Over-irrigation C. Deforestation D. Industrial waste dumping 23 / 25 23. Which microorganism is used as an indicator of fecal contamination in water? A. Escherichia coli B. Bacillus subtilis C. Pseudomonas aeruginosa D. Staphylococcus aureus 24 / 25 24. The Platinum-Cobalt (Pt-Co) scale is used to measure A. Turbidity of groundwater B. Color of drinking water C. Odor intensity in wastewater D. pH-dependent color changes 25 / 25 25. Biomagnification of DDT occurs because it: A. Dissolves readily in water B. Degrades rapidly in fatty tissues C. Volatilizes into the atmosphere D. Binds to blood proteins in predators Your score isThe average score is 52% 0% Restart quiz Author kanwar Kanwar Bhan Godara UGC NET JRF Environmental Science View all posts kanwar Kanwar Bhan Godara UGC NET JRF Environmental Science View All Posts Post navigation Previous Post UGC NET Environmental Science January 2025: Complete SolutionsNext PostOcean Acidification: A Critical Planetary Boundary Already Crossed