GMAT&LAST CR 中的请教答案D的解题思路

20.   When people predict that certain result will not take place unless a certain action is taken, they believe that they have learned that the prediction is correct when the action is taken and the result occurs. On reflection, however, it often becomes clear that the result admits of more than one interpretation.

Which of the following, if true, best supports the claims above?

(A) Judging the success of an action requires specifying the goal of the action.

(B) Judging which action to take after a prediction is made requires knowing about other actions that have been successful in similar past situations.

(C) Learning whether a certain predictive strategy is good requires knowing the result using that strategy through several trials.

(D) Distinguishing a correct prediction and effective action from an incorrect prediction and ineffective action is often impossible.（D）

(E) Making a successful prediction requires knowing the facts about the context of that prediction.

请教D意思和解题思路?

D 一般不可能把正确的预言和行为的有效性从不正确的预言和不适当的行为中区别出来。

题干： 人们预言说一个结果不可能发生除非什么事情发生的时候， 他们认为他们已经确定在行为已经发生， 结果就要出来的正确性。 然而， 事实上结论总是多面性的。

（抱歉， 翻译的很烂）

D 承题干，说看问题的多样性。 别的选项都与此无关

明白了些，谢！