The proposal to extend clinical trials, which are routinely used as systematic tests of pharmaceutical innovation, to new surgical procedures should not be implemented. The point is that surgical procedures differ in one important respect from medicinal drugs: a correctly prescribed drug depends for its effectiveness only on the drug's composition, whereas the effectiveness of even the most appropriate surgical procedure is transparently related to the skills of the surgeon who uses it.

Q. The reasoning in the argument is flawed because the argument

a) does not consider that new surgical procedures might be found to be intrinsically more harmful than the best treatment previously available

답을 유추하는 방법이 뭔지? (무슨 종류의 flaw question 인지??)

참고로 저는 다른 답들을 소거하니까 a만 남더라구요.  하지만 해답 접근 방법을 알아야지 유사한 유형의 문제가 나올때 응용이 될텐데 도통 감이 오지 않네요.^^;; (I could not see why it is flawed, actually it did make a sense to me first)

감사합니다.