Which of the following pairs of an environmental problem and its source is correctly matched?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Wastage of cattle dung – Dung cake used as fuel
When dung is burnt as dung cake, it cannot be used as manure or for gobar gas. So wastage of cattle dung is a result of using dung cake as fuel.
Option (1) Fly ash – Hydroelectric projects in river basins — Incorrect. Fly ash comes from thermal power plants, which burn coal.
Option (2) Inundation of forests – Thermal power plants — Incorrect. Forests are flooded by hydroelectric projects, not thermal plants.
Option (3) Wastage of cattle dung – Dung cake used as fuel — Correct. It is one of the adverse effects of biomass fuel.
Option (4) Transmission loss – Mini-hydel plants in hilly areas — Incorrect. Mini-hydel plants avoid transmission loss, as power is used locally.
NCERT (2026-27): “7.5 Strategies for Sustainable Development … Both of these have adverse environmental impacts. Thermal power plants emit large quantities of carbon dioxide which is a green house gas. It also produces fly ash which, if not used properly, can cause pollution of water bodies, land and other components of the environment. Hydroelectric projects inundate forests and interfere with the natural flow of water in catchment areas and the river basins.” “LPG, Gobar Gas in Rural Areas: Households in rural areas generally use wood, dung cake or other biomass as fuel. This practice has several adverse implications like deforestation, reduction in green cover, wastage of cattle dung and air pollution. …” “… This means that they can also do away with the need for large scale transmission towers and cables and avoid transmission loss.” |