题目

      阅读下面的短文。从所给的A―E五个选项中为标有小题号的段落找出适当的小标题。选项中有一个是多余的选项。57．More than three hundred fifty national parks can be found in the United States．These parks include huge colored rock formations，rivers，waterfalls，beautiful trees，other plants and many different kinds of wild animals．    58．Millions of people from all over the world visit the state of Utah every year．One reason is the many national parks．These are areas of great natural beauty that are protected by the United Sta 机器化生产、工业污染最早出现于 [　　] A． 第一次工业革命 B． 第二次工业革命 C． 第三次科技革命 D． 新航路的开辟