Select the correct statement. A. A meander increases the river length but a cut off reduces the river length B. A cut-off increases the river length but a meander reduces the river length C. Both meander and cut-off increase the river length D. Both meander and cut-off decrease the river length

The correct answer is A. A meander increases the river length but a cut off reduces the river length.

A meander is a bend in a river. It is caused by the erosion of the riverbank on the outside of the bend and the deposition of sediment on the inside of the bend. As the meander grows, it can eventually become so large that it cuts off a section of the river, creating an oxbow lake. The cut-off section of the river then becomes a dead end, and the river length is reduced.

Option B is incorrect because a cut-off reduces the river length, not increases it.

Option C is incorrect because meanders and cut-offs have opposite effects on the river length. Meanders increase the river length, while cut-offs reduce it.

Option D is incorrect because meanders and cut-offs do not have the same effect on the river length. Meanders increase the river length, while cut-offs reduce it.