Question

what is a major risk associated with groundwater use? it can become over run with algae. it can be contaminated by pollutants. it can evaporate leaving sediment behind.

Explanation:

Groundwater is vulnerable to pollution from various sources like industrial waste, agricultural chemicals (pesticides, fertilizers), and improper waste disposal. Once contaminated, it is difficult and costly to clean. Algae over - growth is more common in surface water bodies (like lakes) due to nutrient runoff (eutrophication). Evaporation leaving sediment behind is a natural process in some surface water settings (e.g., drying up of shallow ponds) but not a major risk associated with groundwater use.

Answer:

It can be contaminated by pollutants.