(单选题)

What does the "it" in the second paragraph refer to?

A.The linguistic rules

B.Thinking of exceptions.

C.Sending to do something useful

D.Learning linguistic rules.

参考答案：A

参考解析：

细节理解题。根据第二段第二句“First, it astonishes us that there are rules that we didn’t know that we knew.”可知it为形式主语，真正主语为这些我们不知道我们自己知道的规则。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