问题详情

Which statement does this passage lead you to believe？
A．It won"t be easy to get rid of the tsetse flies in Africa.
B．Sleeping sickness is unknown to Africans.
C．People did not know sleeping sickness could cause deaths.
D．The people there did not know the tsetse carried a kind of disease to man.请帮忙给出正确答案和分析，谢谢！