Which geographic feature encouraged westward movement? options are waterfall, rivers, mountains, basins.

I am pretty sure basins are the correct answer

mali had been a state inside of the ghanaian empire. after ghana fell because of invading forces and internal disputes, mali rose to greatness under the leadership of a legendary king named sundiata, the "lion king." the songhai empire, already weakened by internal political struggles, went into decline.

i am pretty sure it is d.