75.This passage is mainly about .
(A)the development of body language
(B)the special role humans play in nature
(C)the power to convey information to others
(D)the difference between humans and animals in language use

整篇文章谈论的都是给他人传递信息的力量, 使用语言的能力。A, B选项文章未提及. D选项较片面, 文章第三段中提到了相似点和差异二种。