Question

what is an effect of water pollution?
a. toxic metals build up in the food chain.

b. more floods occur along rivers and streams.

c. climate change increases water temperatures.

d. polluted water evaporates and becomes acid rain.

Explanation:

• Option A: Water pollution can introduce toxic metals into water bodies. These metals can be absorbed by aquatic organisms, and as organisms at lower trophic levels are eaten by those at higher levels, the toxic metals bioaccumulate and biomagnify in the food chain.
• Option B: Floods are more related to factors like excessive rainfall, poor drainage, or changes in land use (like deforestation) rather than water pollution.
• Option C: Climate change leading to increased water temperatures is a cause - effect relationship in the opposite direction of what is asked, and also climate change is a broader issue not directly an effect of water pollution.
• Option D: Acid rain is mainly caused by air pollutants (like sulfur dioxide and nitrogen oxides) reacting with water in the atmosphere, not by the evaporation of polluted water.

Answer:

A. Toxic metals build up in the food chain.