Which of the following situations is a direct example of water pollution?

• A. Overgrazing by cattle leads to soil erosion.
• B. Noise from traffic disturbs a nearby wetland.
• C. A forest fire releases smoke into the atmosphere.
• D. A factory discharges untreated waste into a river.

Answer: (D)

Verified step by step guidance

1. Understand the concept of water pollution: Water pollution occurs when harmful substances contaminate water bodies such as rivers, lakes, or oceans, making the water unsafe for organisms and ecosystems.
2. Analyze each option provided in the problem: Determine whether each situation directly impacts water quality or introduces pollutants into a water body.
3. Option 1: Overgrazing by cattle leads to soil erosion. This primarily affects soil and land quality, not directly contaminating water bodies.
4. Option 2: Noise from traffic disturbs a nearby wetland. Noise pollution affects the environment but does not introduce harmful substances into water bodies.
5. Option 4: A factory discharges untreated waste into a river. This is a direct example of water pollution because untreated waste introduces harmful substances into the river, contaminating the water and affecting aquatic life.