Concept:Soil erosion in the tropics is mainly caused by land-use practices that leave the soil bare or weaken its protective cover.
The removal of vegetation exposes the fertile topsoil to the forces of rain and wind.
Explanation:Bush fallowing exposes the soil when the fallow period becomes too short for the land to recover its vegetation cover.
Overgrazing removes grass roots and leaves the soil unprotected and prone to erosion.
Monoculture, the continuous planting of the same crop, depletes soil nutrients and destroys the soil structure.
These activities lower soil fertility and increase its exposure to the agents of erosion.
Therefore, they are the land-use practices most responsible for soil erosion in the tropics.
Answer:D. bush fallowing, overgrazing and monoculture