If location "C" is the liquid state and location "E" is the gas state, then what phase change is
happening at "D" as heat is removed?
O solidification
O fusion
O condensation
O vaporization

The correct option is C.
A deep river is one which has slow movement or is stagnant. In such a river mud or silt are usually present, this is because they have time to settle down because of the slow movement or stagnancy of the water. Thus, fish that feed on sediments are usually found in such rivers.