(单选题)

The example of Arctic terns in the last paragraph is used mainly to show ______.

A.the distance of migration

B.the purpose of migration

C.the direction of migration

D.the time of migration

参考答案：A

参考解析：

概括归纳题。根据最后一段第一句“Arctic terns travel the furthest when they migrate”以及第四句“In one year these small birds travel 36,000 km from one end of the earth to the other and back again”可知，本段主要讲了北极燕鸥的迁徙距离。故选A。

知识点：阅读理解四选一英语专业基础知识阅读理解教师招聘-小学英语