国际辐射单位和测量委员会的英文缩写是（）

A.IGRT

B.IGRU

C.IAEA

D.ICRU

E.IMRT

完成句子：根据句意及汉语提示，用词组的适当形式填空。（每小题2分）

小题1:. Mrs. White is a kind woman. She spends most of her free time                    （照顾）these homeless dogs.

小题2:. There is                     (毫无疑问)that the engineer has made a mistake once again.

小题3:The boy’s parents are dead, so he has to                          （依靠）himself.

小题4:. Zheng He was the Ming Dynasty explorer whom all the Chinese people

（对……感到骄傲）.

小题5:. Now more and more persons walk or ride a bicycle to work                    （代替）driving a car.