题目

Tony Buzan’s grades were going down                                       at university. Disappointed with his low marks, he went to the library to find a book on how to use his brain. He was directed to the medical section. Confused, he said to the librarian, “I don’t want to take my brain out, I just want to learn how to use it.” Her reply was simple: “There’s no book on that.”                                                 “I thought to myself,” says Buzan, “if I buy a little ra参加2008年北京第29届奥运会的A，B，C，D四名运动员国籍各不相同，分别是美，韩，法，日．当然这里的名字顺序不一定与上面写的国籍顺序相同．已知：A和美国运动员都是排球运动员，B和日本运动员都是柔道运动员且比韩国运动员高，C不是排球运动员，则A是________，B是________，C是________，D是________．