The river overflowed its . . . . . . and flooded the area.

The correct answer is A. banks.

The banks of a river are the land that borders the river on either side. When a river overflows its banks, it floods the area next to the river. This can cause damage to property and infrastructure, and can also lead to loss of life.

The other options are incorrect because they do not refer to the land that borders a river. Limits refers to the boundaries of something, edges refers to the outer parts of something, and fronts refers to the parts of something that face forward.