What does the term “behavior” in the second paragraph especially refer to in this passage?

A.It refers to observable and physical movements and acts

B.It refers to the part of language behavior that involves understanding or interpretation

C.It refers to both the overt and the unobservable language behaviors in communicating

D.It refers to acts of speaking and writing

正确答案：It refers to both the overt and the unobservable language behaviors in communicating