根据短文内容，选择正确的答案。   

B

    A crow (乌鸦) wants to drink, but he can't find water. He looks here and there. At last, he cries, "I can see a jar (罐子) and there is some water in it." He tries to get the water, but he can't. "How can I get the water?" he cries, "I can put my break (鸟嘴) quite close it." But still he cannot drink. "What can I do? I want to drink." He looks here and there, then he picks up a small stone (石头) in his break and carries it to the jar of water and drops it into the jar. "Soon the water will be high in the jar, and I can drink," says the crow. So he begins to do that until the water is high (高的) enough to drink.