题目

阅读理解；阅读下列材料，从每题所给的A、B、C三个选项中选出最佳答案。     Of course you do not want to spend your vacation sick (生病的) in bed. So what can you do to stay in good health when traveling? There are some things you should remember when you travel: relax, sleep and eat well.    A vacation should be a time for relaxing but very often it is not. Think about what you do when you are traveling. There are so many places to visit: museums, shops, parks ... You may spend most days walking around these places. This can be very tiring. Do not ask you现有四个函数：①y＝xsin x，②y＝xcos x，③y＝x|cos x|，④y＝x2x.它们的部分图像如图所示，但顺序被打乱，则按照从左到右将图像对应的函数序号排列正确的一组是(　　)A．④①②③B．①④③②C．①④②③D．③④②①