Communicating via E-mail is by far the most common Internet activity. You can （1) with any

Communicating via E-mail is by far the most common Internet activity. You can (1) with anyone in the world who has an Internet address or E-mail (2) with a system connection to the Internet. All you need is (3) the Internet and an E-mail program Two of the most widely used E-mail programs are Microsoft's (4) and Netscape's Navigator. A typical E-mail message has three basic (5) ：header, message, and signature.

A．connect

B．exchange

C．communicate

D．game