What is sprain?what are the causes, symptoms and treatments

A sprain is a stretching or tearing of ligaments — the tough bands of fibrous tissue that connect two bones together in your joints. The most common location for a sprain is in your ankle. Initial treatment includes rest, ice, compression and elevation. Mild sprains can be successfully treated at home

Explanation:

answer; i believe that the correct answer is (b) melosis; plz check first.good luck

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."