题目内容：
1.What‘s the author‘s purpose in writing this passage? 【外语教育&网www.for68.com】A) To show the inability of trains to compete with planes with respect to speed and convenience.
B) To stress the influence of the automobile on America‘s standard of convenience.
C) To emphasize the function of travel agencies in market promotion.
D) To illustrate the important role of persuasive communication in changing consumer attitudes.
参考答案：