求教OG-172

172. There is a great deal of geographical variation in the frequency of many surgical
procedures—up to tenfold variation per hundred thousand between different areas in the numbers of hysterectomies, prostatectomies, and tonsillectomies.
To support a conclusion that much of the variation is due to unnecessary surgical
procedures, it would be most important to establish which of the following?
(A) A local board of review at each hospital examines the records of every operation to determine whether the surgical procedure was necessary.
(B) The variation is unrelated to factors (other than the surgical procedures themselves) that influence the incidence of diseases for which surgery might be considered.
(C) There are several categories of surgical procedure (other than hysterectomies, prostatectomies, and tonsillectomies) that are often performed unnecessarily.
(D) For certain surgical procedures, it is difficult to determine after the operation whether the procedures were necessary or whether alternative treatment would have succeeded.
(E) With respect to how often they are performed unnecessarily, hysterectomies,
prostatectomies, and tonsillectomies are representative of surgical procedures in general.

我明白B是答案。但是C不是一种加强方式吗？C说这三种手术和其它的几类手术也经常是不必要的手术。这难道不是以个直接加强结论的事实型加强吗？谢谢！

谢谢你的回答。但是这是个加强题啊？加强题还要考虑必要条件吗？难道加强题有时也要与假设题一样用取非削弱来验证是否加强结论来判断答案正确与否吗？我做假设和加强题思路还不是很清晰，你能具体讲一讲如何考虑此两种题型吗。谢谢指教！

The question is "to support the conclusion, it is important to establish that ...". It is identical to "which of the following has to be true in order to draw the conclusion properly". Therefore, the question is asking for the required condition.

Support is not the same as strengthen. A premise is support to conclusion. Furthermore, I do not think that C strengthens the argument. It is not that relevant. For example:

Conclusion: When he eats too much peas, he feels bloated.
Support A: Peas, when consumed, generate gas in the intestine.
Support B: He does not feel bloated when he does not eat peas.
Strengthen: When he does not eat peas, he does not feel bloated.  

You are right. The support B should read: When he does not feel bloated, he does not eat peas. Good catch!

我当时也选了C。
但是后来分析一下，题目文的是much of the variation is due to unnecessary surgical procedures。
而C当时仅仅说明了有其他的不必要的手术步骤，而没有强调这些步骤和variation的关系。也就是有些偏题了。

Let's Fight,
Demon Hunter