Answer:
Sewage, oil, pesticides and fertilizers affect water quality.
Explanation:
There are three types of pollution i. e. air pollution, soil pollution and water pollution. Smoke and smog are present in the air is the example of air pollution, waste product, using of pesticide and industrial dumping are the example of soil pollution and chemicals in water due to runoff of fertilizer, sewage and oil are the main agents of water pollution. These three types of pollution adversely affected the water quality. Water quality will be affected when the fertilizer or pesticides runoff from land to water bodies. Sewage and oil also lowers the quality of water.
The answer is C, because if something contagious we’re to threaten the population of the species then not having any variant means they’re all the same and it would kill them all and cause them to go extinct
