Which one is NOT a cause of water pollution?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Rainfall
Water gets polluted when harmful substances enter it. Some come from natural sources, but most come from human activities.
Option (1) Urbanisation — A cause of water pollution. Growing towns send sewage and urban run-off into rivers.
Option (2) Landslides — A cause of water pollution. Landslides and erosion are natural sources of water pollutants.
Option (3) Rainfall — Not a cause of water pollution. Rain itself is not a source of pollutants. The pollutants come from erosion, landslides, sewage, run-off over farms and towns, and industrial effluents.
Option (4) Industrialisation — A cause of water pollution. Industry is the most significant contributor to water pollution, through toxic effluents.
NCERT (2026-27): “Though water pollutants are also created from natural sources (erosion, landslides, decay and decomposition of plants and animals, etc.) pollutants from human activities are the real causes of concern. Human beings pollute the water through industrial, agricultural and cultural activities. Among these activities, industry is the most significant contributor.”
Table 9.1 : Types and Sources of Pollution |
