读图，完成以下问题。

很多动物为了适应自身生存的环境，进化出了符合一定物理规律的身体部位，对此，从物理学的角度给出的解释中正确的是（　　）

阅读材料，回答问题

材料：与外界隔绝，曾是保存旧中国的首要条件……一个人口几乎占人类三分之一的大帝国，不顾时事，安于现状，人为地隔绝于世并因此竭力以天朝尽善尽美的幻想自欺。这样一个帝国注定最后要在一场殊死的决斗中被打垮。

①从材料中提取一个论点。

②综合上述材料，自拟观点，进行论述。

       My friend Tony is an American   1  . He is ten years old. He lives  2  his family in China now. There are   3   people in his family; his mother Mrs. Green, his father Mr. Green and his little sister Amy. He has a white cat.  4  name is Betty. Look！Amy is playing   5  Betty. His father, Mr. Green, is watc­hing TV. His mother is doing housework. What about Tony? He is doing   6 Chinese homework. He can't  7 Chinese well, but he likes Chinese very much. Tony's 8 works in a TV station. His father works in a school as an   9  teacher. Tony and his sister 10  to the same school.