Read the passage and answer the questions:
Water Pollution
Indiscriminate use of water by increasing population and industrial expansion has led degradation of the quality of water considerably. Surface water available from rivers, canals, lakes, etc. is never pure. It contains small quantities of suspended particles, organic and inorganic substances. When concentration of these substances increases, the water becomes polluted, and hence becomes unfit for use. In such a situation, the self-purifying capacity of water is unable to purify the water. 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. Industries produce several undesirable products including industrial wastes, polluted waste water, poisonous gases, chemical residuals, numerous heavy metals, dust, smoke, etc. Most of the industrial wastes are disposed off in running water or lakes. Consequently, poisonous elements reach the reservoirs, rivers and other water bodies, which destroy the bio-system of these waters. Major water polluting industries are leather, pulp and paper, textiles and chemicals. Various types of chemicals used in modern agriculture such as inorganic fertilisers, pesticides and herbicides are also pollution generating components. These chemicals are washed down to rivers, lakes and tanks. These chemicals also infiltrate the soil to reach the ground water. Fertiliser induces an increase in the nitrate content of surface waters. Cultural activities such as pilgrimage, religious fairs, tourism, etc. also cause water pollution. In India, almost all surface water sources are contaminated and unfit for human consumption.
Which of the following is an example of water pollution from natural source?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Landslide
Option (1) Industrial Activities — Incorrect. Industry is a human activity, and the passage calls it the most significant contributor to water pollution.
Option (2) Agriculture — Incorrect. Agriculture is also a human activity; its fertilisers, pesticides and herbicides wash down into rivers, lakes and tanks.
Option (3) Landslide — Correct. Water pollutants are also created from natural sources: erosion, landslides, and the decay and decomposition of plants and animals.
Option (4) Cultural Activities — Incorrect. Pilgrimage, religious fairs and tourism are human activities that pollute water, not natural sources.
Note: This passage is taken almost word for word from the section on water pollution in the NCERT chapter ‘Geographical Perspective on Selected Issues and Problems’ (India – People and Economy). NTA served the opening lines on water pollution as an ‘unseen’ passage, already seen by everyone who read that chapter once with care. A slow first reading of each chapter pays back in marks.
NCERT (2025-26): “Water Pollution Indiscriminate use of water by increasing population and industrial expansion has led degradation of the quality of water considerably. Surface water available from rivers, canals, lakes, etc. is never pure. It contains small quantities of suspended particles, organic and inorganic substances. When concentration of these substances increases, the water becomes polluted, and hence becomes unfit for use. In such a situation, the self-purifying capacity of water is unable to purify the water. Water Pollution … 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.” |