题干

如图所示,坐在甲火车中的小华在车窗里看到乙火车的车头,过一会儿,她又在车窗里看到乙火车的车尾。若两火车车头朝一个方向,下列关于它们运动情况的判断,不可能的是    (    )

A:甲火车停在轨道上,乙火车向前运动

B:两列火车均向前运动,但甲火车运动较慢

C:两列火车均向后倒车,但甲火车运动较慢

D:甲火车向后倒车,乙火车停在轨道上

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C

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    Health experts are calling for action to increase cancer care and control in the developing world. A medical research paper says cancer was once thought of as a problem mostly in the developed world. But now cancer is a leading cause of death and disability in poor countries as well. Experts from Harvard University and other organizations urge the international community to fight cancer actively, saying it should be fought in the way HIV/AIDS has been fought in Africa.

    Cancer kills more than 7.5 million people a year worldwide. Almost two thirds are in low-income and middle-income countries.

    They discover cancer kills more people in developing countries than AIDS, tuberculosis and malaria combined. But the world spends only 5﹪ of its cancer resources in those countries.

    Felicia Knaul from Harvard Medical School was one of the writers of the paper. She was in Mexico when she was found to have breast cancer. She received treatment there and her experience showed her the sharp difference between the rich and the poor in treating breast cancer.

    Felicia Knaul says, “And we are seeing how this is attacking young women. It's the number two cause of death in Mexico of women thirty to fifty-four. All over the developing world, it's the number one cancer-related death among young women. I think we have to again say that there is much more we could do about it than we are doing about it. ”

    Professor Knaul met community health workers during her work in developing countries. They were an important part of efforts to reduce deaths from the cancer. They were able to persuade people to get tested to prevent the illness. The experts say cancer care does not have to be costly. For example, patients can be treated with lower-cost drugs.