Which of the following is a biodegradable pollutant?A: PlasticB: SewageC: AsbestosD: Mercury

The correct answer is B: Sewage.

Sewage is considered a biodegradable pollutant because it consists of organic matter such as human waste, food scraps, and other natural materials that can be broken down by microorganisms through natural biological processes. These microorganisms, such as bacteria and fungi, feed on the organic matter present in sewage and decompose it into simpler compounds, eventually returning it to the environment in a more natural and harmless form.

On the other hand, options A, C, and D are not biodegradable pollutants:

A: Plastic is a non-biodegradable pollutant, as it is made of synthetic polymers that do not easily break down in the environment. Plastics can persist for hundreds of years, causing significant pollution and harm to ecosystems.

C: Asbestos is a mineral fiber that was commonly used in building materials for its heat resistance and durability. However, asbestos is not biodegradable and can cause severe health issues when its fibers are released into the air and inhaled.

D: Mercury is a heavy metal that is toxic to living organisms. While it can undergo certain transformations in the environment, it is not considered biodegradable in the same way organic materials are. Mercury can accumulate in the food chain, causing harm to humans and wildlife.