Your friend says that he thinks his personalitychanges when he's around different people

In the best relationships, we tend to

a. give more than we receive. b. create a social reality. c. demand more than we receive. d. avoid social exchange. e. both give and receive rewards.

According to one prominent theory, monogamy evolved in only those species

A) in which each female could raise more fit young if she had undivided help. B) with opposable thumbs. C) with large brains. D) that used tools. E) all of the above