单选题
[概括大意]It is not difficult to think of other messages we receive through the mass media. Every day we get hundreds of them. Think about advertisements， for example. We see and hear these messages almost everywhere we go. Advertisements are important messages， even though they are sometimes annoying. They help us compare and evaluate products.
The main idea of this paragraph is__________.
A、Importance of the Mass Media
B、Media — Means to Communicate Messages
C、Advertisements as Important Messages from the Mass Media
D、Various Messages One May Receive Each Day
正确答案：C
答案解析：选项借用了段中的词 Advertisements、important messages。本段主要介绍了广告是大众媒体的重要媒介。