请教大家一道逻辑题~

wanghui318

12.The organizers of tomorrow's outdoor concert
announced that it will go on tomorrow on schedule
unless bad weather is forecast or too few advance
tickets are sold. If the concert is canceled, refunds
will be made to ticket holders. Since some ticket
holders have already been issued refunds even though
more than enough advance tickets were sold, it must
be the case that bad weather is forecast.
Which of the following is an error of reasoning con-
tained in the argument?
(A) It proceeds as if a condition, which by itself is
enough to guarantee a certain result, is the only
condition under which that result would occur.
(B) It bases a conclusion that is known to require
two conditions on evidence that bears on only
one of those conditions.
(C) It explains one event as being caused by another
event, even though both events must actually
have been caused by some third, unidentified
event.
(D) It treats evidence for the absence of one condi-
tion under which a circumstance would occur
as conclusive evidence that that circumstance
will not occur.
(E) Evidence given to support the conclusion actually
undermines it.
答案是A，但是整体文章我感觉并没有错误，自己的理解如下
天气 OR 售票不佳 导致取消演出——事实：退票（但售票充足）——结论：天气原因

franciszmy

有逻辑漏洞的。充分必要问题。A:（天气 OR 售票不佳 导致取消演出）----这是主办方提出的---充分条件---也就是说主办方如果碰到这两条件中的一个会取消演出。
                           B: 事实：退票（但售票充足）——这是持票者提出的---必要条件  这里有个问题，持票者买了大多数的票，演出取消就一定是因为坏的天气吗？不尽然，没准是其他因素造成的。
题目给的前提条件是A===>B， 但是B反向能不能推出A，这个就不能确定了。题目只是限定了主办方取消演出的条件，并没有限定持票者的条件，所以从持票者的角度分析取消演出的原因，我们是没法判定的

wanghui318

分析的很透彻，十分感谢~