Soil erosion by action of rain can be caused by all of the following except
tropical rainstorms
scanty vegetation
steep slopes
aridity
Correct answer is D
Soil erosion by the action of rain, also known as water erosion, is primarily caused by the removal of vegetation, steep slopes that increase the speed of runoff, and heavy rainstorms. Aridity, on the other hand, refers to dry conditions, which are less likely to cause soil erosion by rain. Therefore, the correct answer is 'aridity'.