问题补充：
E-mail, as well as telephones, an important part in daily communication.
A. is playing
B. have played
C. are playing
D. played
答案：
(答案→)A. is playing
B. have played
C. are playing
D. played
解析：句意：电子邮件和电话在我们日常交流中都起到了非常重要的作用。as well as和，连接两个主语时候，句子中心在前面，谓语动词的数只与第一个主语的数表示一致。故选A
