Correct Answer: Both (1) and (2)

Solution : The correct answer is Both (1) and (2).

Eutrophication is also known as nutrient enrichment of a water body. It is caused because of the increased supply of nutrients through agricultural runoff and industrial wastes into the water body. It increases the rate of organic matter production because of increased uptake of nutrients by marine plants and animals and it also increases its biological oxygen demand. It is a negative phenomenon which leads to the death of a water body.