免疫是机体的一种重要的保护性功能，下列不属于人体免疫功能的是：（　　）

我市统计局发布的统计公报显示，2004年到2008年，我市GDP增长率分别为9.6%、10.2%、10.4%、10.6%、10.3%. 经济学家评论说，这5年的年度GDP增长率相当平稳，从统计学的角度看，“增长率相当平稳”说明这组数据的（）比较小.

阅读短文，选择正确答案。

    The bell rings (响). Mr. Wang goes into Class Three and wants to give an English lesson. At this time Mr. Zhang comes and asks him to attend (参加) an important (重要的) meeting. So Mr. Wang says to his students, "Study by yourselves, please."

     When Mr. Wang comes back,he sees Zhao Yang talking with his desk mate Li Cheng.

   “Stand up, Zhao Yang," says Mr. Wang, "What are you doing?"

    "I'm reading English," says ZhaoYang.

    "What's in your hand?" says Mr.Wang.

     ZhaoYang looks at his hand. It's a history book.Then he looks at Li Cheng. There is an English book in his hand. So he says, “Sorry, Mr. Wang. We are studying the history of England."

读“台湾岛主要农作物、水果和矿产分布图”，回答下列问题．