Concept:Biodegradable pollutants are organic materials broken down by microorganisms in water.
This decomposition can make the water unsafe for humans and aquatic life.
Explanation:Microorganisms such as bacteria and fungi feed on biodegradable pollutants.
Their activity reduces dissolved oxygen in the water as they decompose the waste.
This harms fish and other aquatic organisms.
It can also create conditions that favour disease-causing organisms.
People who drink or use such polluted water may develop waterborne diseases.
Therefore, biodegradable pollutants can directly endanger human health.
Answer:C. ill health