Growing crops on a regular basis in mesopotamia could only be done a: after the nomadic akkadian has been driven out of the area. B: when people controlled the flow of the rivers C: when warrning city states worked together D: after the invention of the iron plow

B, when people controlled the flow of the rivers.

The problem with mesopotamia was that although it had incredible natural defenses, it was in the middle of an enormous flood plain, so the people needed a way to control how much water came in and out of the farmlands.