What Effect Have the Historically Low Human Population Densities and the Presence

What effect have the historically low human population densities and the presence of several endemic diseases among humans in Africa had on the survival of African wildlife?

A) They have helped African wildlife to survive.
B) They have had no effect on African wildlife.
C) They have made it more difficult for African wildlife to survive.
D) Low human population densities have made it easier for African wildlife to survive, while endemic diseases have made it harder for African wildlife to survive.
E) Low human population densities have made it harder for African wildlife to survive, while endemic diseases have made it easier for African wildlife to survive.