Question

这题为什么选A，不是B？急

It is thought that crying is hardly an activity encouraged by society. Tear, whether they are of sorrow, anger, or joy, typically make Americans feel uncomfortable and embarrassed. The shedder of tears (落泪者) is likely to apologize, even when a great tragedy was the cause. The observer of tears is likely to do everything possible to put an end to the emotional tears. But judging from recent studies of crying behavior, both those responses to tears are often inappropriate and may even be counterproductive (适得其反).
Humans are the only animals clearly known to shed emotional tears. Since evolution has given rise to few purposeless physiological responses, it is logical to assume that crying has one or more functions that enhance (increase) survival.
Although some observers have suggested that crying is a way to ask for assistance form others (as a crying baby might from its mother), the shedding of tears is hardly necessary to get help. Vocal cries would have been quite enough, more likely than tears to gain attention. So, it appears, there must be something special about tears themselves.
Indeed, the new studies suggest that emotional tears may play a direct role in alleviating stress, University of Minnesota researchers who are studying the chemical composition of tears have recently isolated two important chemicals from emotional tears. Both chemicals are found only in tears that are shed in response to emotion. Tears shed because of exposure to cut onion would contain no such substance.
Other researchers are investigating the usefulness of tears as a means of diagnosing human ills and monitoring drugs. At Tulane University’s Teat Analysis Laboratory Dr. Peter Kastl and his colleagues report that they can use tears to detect drug abuse, to study the causes of “dry eye” syndrome（综合症）and the effects of eye surgery, and perhaps even to measure exposure to environmental pollutants.
65．From the passage we can infer that .
A．it is unnatural for people to shed tears
B．we can reduce our stress by shedding tears
C．shedders of tears can’t get help by crying loudly
D．unlike animals, humans can shed tears for survival

Answer 1

It is thought that crying is hardly an activity encouraged by society. Tear, whether they are of sorrow, anger, or joy, typically make Americans feel uncomfortable and embarrassed. The shedder of tears (落泪者) is likely to apologize, even when a great tragedy was the cause. The observer of tears is likely to do everything possible to put an end to the emotional tears. But judging from recent studies of crying behavior, both those responses to tears are often inappropriate and may even be counterproductive (适得其反).
社会认为哭泣是不值得鼓励的举动。不管是出于悲伤，愤怒，快乐，眼泪通常让美国人觉得尴尬不安。即使是巨大的悲剧导致哭泣，哭泣者也会道歉。而旁观者会竭尽所能让他停止情绪化的哭泣。但是最近的关于哭泣行为的研究表明，哭泣者和旁观者的上述两种反应经常是不恰当的，而且会适得其反。

Humans are the only animals clearly known to shed emotional tears. Since evolution has given rise to few purposeless physiological responses, it is logical to assume that crying has one or more functions that enhance (increase) survival.
人类是唯一能够因为情绪而哭泣的动物。由于进化减少了无目的的生理反应，我们有理由假设哭泣除了提高生存率外，还有一个或更多其他的功能。

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UNNATURAL有不自然的意思，可以理解成为是自然界的动物没有的，人类在进化过程中才形成的。当然这个题目有点牵强，出的不好。
至于B，因为题干里面是INFER，要推断的，而
Indeed, the new studies suggest that emotional tears may play a direct role in alleviating stress, 这句跟B是同一个意思，已经不需要推断了，所以排除