The retinas of premature babies are not fully developed at birth. Because their retinas are 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?
When premature babies are born, their retinas are developmentally unprepared to deal with light and air in the environment outside the womb.
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.
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.
The improvement of methods to prevent retinopathy of prematurity has been a gradual process, and there is still a need for further knowledge.
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.
我的想法,简单来说就是以前生的早产儿可能是八九个月的,retina假设发育了80%;现在医疗技术进步了,五六个月的早产儿都能活下来,他们的retina只发育了40%,早产儿中更弱的比例变大了,就算Methods for preventing this syndrome提升了,也无力阻止这些太弱的孩子眼睛出问题。
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