不同的生物的适应能力不同。下列哪组生物在地球上分布范围极为狭窄? (    )

    My friend Tom is a schoolboy. Everyone likes him very much because he is kind. He likes to help people. He is a smart boy and he can play many musical instruments(乐器). After school, when he is with his friends, he often plays musical instruments for them. On weekends, he is free and he always goes to the old people's home. He plays the violin and the guitar to make them happy. He thinks it's interesting and fun.

    Today is February 28th. It's Tom's birthday. He has a big and interesting party at home. Many friends come to his party. Tom's mother cooks a lot of food for them. Everyone gives a beautiful gift to him. Sally gives him an English dictionary because Tom also likes English. Bob gives Tom a guitar because he likes playing the guitar very much. At the party, Tom plays the guitar and he also plays the piano. We sing many songs and play some interesting games. We have a good time today.

如图所示的实验，是我们在学习分子动理论时做过的一些实验：

图a：浓硫酸铜溶液与清水开始界面十分清晰，几天之后，两种液体混合均匀了；

图b：玻璃板的下表面接触水面，发现拉力大于玻璃板的重力；

图c：水和酒精充分混合后的总体积小于混合前水和酒精的总体积；

图d：将红墨水滴入水中，可以看到它在水中扩散开来；

图e：将两个底面干净、平整的铅块紧压在一起，两个铅块就会结合在一起，下面吊一个较重的物体也不会将它们拉开．