单选题 Communication via e-mail is by far the most common Internet activity. You can (71 ) with anyone in the world who has an Internet address or e-mail (72) with a system connection to the Internet. All you need is (73) the Internet and an e-mail program. Two of the most widely used e-mail programs are Microsoft's (74) and Netscape's Navigator. A typical e-mall message has three basic (75) : header, message, and signature.

【正确答案】 B

【答案解析】[解析] 通过电子邮件交流是到目前为止因特网上最普遍的活动。你只要有一台连入Internet的计算机系统，就可以与世界上任何一个有因特网地址或电子邮件账号(account)的人进行交流 (communicate)。所有你所需要的是一个到因特网的接入(access to)和一个电子邮件程序。世界上两个用的最广的电子邮件程序是微软公司的Outlook Express和网景公司的Navigator。一个典型的电子邮件消息有3个最基本的组成部分(elements)：信头、消息和签名。