One similarity between the ancient African kingdoms of Ghana, Mali, and Songhai is that all of these kingdoms were located: A: in coastal areas.

B: in rain forest areas.

C: on major trading routes.

D: in mountainous terrain.

nothing certain is known about what happened, but it seems that the country declined gradually, perhaps due to bad government, or, more likely, due to a series of bad harvests, which resulted in widespread and recurrent famine.

i believe your answer is d)