【单选题】Africa's elephants are divided between the savannahs of eastern and southern Africa and the forests of central Africa. Some biologists reckon the forest ones-smaller, with shorter, straighter tusks-ma...
A.
Biological evidences are insufficient to support this point of view.
B.
The high price of ivory entices more killings of elephants.
C.
Their number is too small to be of a species.
D.
A serious disease broke out among the elephants and sharply decreased their number.