C. More natural disasters.

D. Lower agricultural output.　【试题解析】细节理解题。根据第一段第三句“The country’s farmers are getting older， and there are fewer people standing in line to take their place”可知，A项正确。

1.2间接法——间接信息题

以例说题：(2012年江苏高考英语试卷)

Joan Mclean think so. In fact， Mclean， a professor of physics at Mountain University in Range， feels so strongly about this matter that she’s developed a course on the topic. In addition to learning “who”invented”what”， however， Mclean also likes her students to learn the answers to the”why” and ”how” questions. According to Mclean，”When students learn the answers to these questions， they are better prepared to recognize opportunities for inventing and more motivated to give inventing a try.”

57. Professor Joan McLean’s course aims to_____.

A. add colour and variety to students’ campus life

B. inform students of the windshield wiper’s invention

C. carry out the requirements by Mountain University

D. prepare students to try their own invention

【试题解析】细节题。根据题干可以定位到原文第二段，However处正是考点出题处，引号当中的内容正是证明了Mclean的观点：when students learn the answers to these questions， ... prepared to recognize…inventing a try.由此可以看出选项D正是原文的同义替换。

二、结束语