请教费费逻辑贝多芬头发和水银那道

大家还记得贝多芬头发和水银那道题吗？为什么答案是B some people did not ingest mercury at that time?

I really cannot understand.

The given answer is B. But why? Tks.

21. Historian: We can learn about the medical history of individuals through chemical analysis of their hair. It is likely, for example, that Isaac Newton’s psychological problems were due to mercury poisoning; traces of mercury were found in his hair. Analysis is now being done on a lock of Beethoven’s hair. Although no convincing argument has shown that Beethoven ever had a venereal disease, some people hypothesize that venereal disease caused his deafness. Since mercury was commonly ingested in Beethoven’s time to treat venereal disease, if researchers find a trace of mercury in his hair, we can conclude that this hypothesis is correct.

Which one of the following is an assumption on which the historian’s argument depends?

(A) None of the mercury introduced into the body can be eliminated.

(B) Some people in Beethoven’s time did not ingest mercury.

(C) Mercury is an effective treatment for venereal disease.

(D) Mercury poisoning can cause deafness in people with venereal disease.

(E) Beethoven suffered from psychological problems of the same severity as Newton’s.

历史学家：可以通过研究人的头发知道其病史。例如，IN的精神问题是因为水银中毒；在他的头发中找到了水银。现在正在研究B的头发，尽管没有证据显示B曾患VD，一些人猜测正是VD导致了他的耳朵失聪。因为在B的时代普遍使用水银来治疗VD，如果研究人员在B的头发中找到水银的话，可以结论说这种假设是对的。

选择的时候用排除法，一开始错选D，看了大家的解释 提醒说原文的假设内容是 VD导致了他的耳朵失聪 不是水银。所以只好选B

也不太明白为什么 请大家再给细讲

我没看过大家的讨论，说说个人观点

我也是用排除法做，B is best

B中说在贝多芬的时代有些人不吃(?)水银

如果否定B，在贝多芬时代都吃水银，所以在贝多芬头发里就算发现水银也不代表他有这个病，这就削弱了原文想由此推出的结论，所以B是assumption

sorry!!还是不明白，“如果否定B，在贝多芬时代都吃水银，所以在贝多芬头发里就算发现水银也不代表他有这个病，这就削弱了原文想由此推出的结论”?

但是原文已说 B的时代普遍使用水银来治疗VD

把B取非：

some people ingest mercury in B's time , so B 's hair containing mercury may not because he had to treat his desease V but because  he had a habit of ingesting mercury like other people in his time.

The conclusion that B has desease V thus leading to his deafeness is weakened.