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The retinas of premature babies are not fully developed at birth. Because their retinas arc so delicate, premature babies sometimes lose their sight. Methods for preventing this syndrome, which is called retinopathy of prematurity, have improved, but the proportion of premature babies who lose their sight because of this syndrome has increased. Which of the following, if true, best reconciles the apparent discrepancy described above?
A. When premature babies are born, their retinas are developmentally unprepared to deal with light and air in the environment outside the womb. B. The oxygen that must be administered to premature babies at birth can sometimes have a damaging effect on the babies’ retinas, but the oxygen is now administered in less damaging concentrations than it used to be. C. The effects of retinopathy of prematurity can be reduced by controlling the exposure of premature babies to light and oxygen, but this method cannot completely prevent the syndrome. D. The improvement of methods to prevent retinopathy of prematurity has been a gradual process, and there is still a need for further knowledge. E. Improved medical technology is saving the lives of premature babies who would previously have died, but these babies have even more delicate retinas than do other premature babies and are more apt to lose their sight.
标答似乎是B，个人选了E
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发表于 2018-11-24 23:07:21
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