Answer :
"American literature often portrays aspects of the American identity"is the proper answer. Literature of most kinds is meant to be a reflexive mirror, towards which society is meant to look.
American literature and literature, in general, holds a close relationship with the reality it's been written in. It projects the writer's identity, desires and beliefs, this is not only reflected in the actions of the characters in some cases but also in the language they use, how they develop under certain situations, the direct beliefs stated in the text in some cases. As the author is a part of a society that in a way or another influences the way he creates his identity, its easy to say his creation also projects the American identity
The correct answer is A: American literature often portrays aspects of the American identity.