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 the 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.

Which of the following place is the chief cause of pollution in the Yamuna river?

Delhi

The correct answer is option 3: Delhi

Delhi is the chief cause of pollution in the Yamuna River. Although the Yamuna flows through several cities, the stretch passing through Delhi receives a very large amount of untreated and partially treated domestic sewage, industrial effluents, and wastewater through numerous drains. As a result, a major portion of the river's pollution load is added within Delhi.