Question

一道GMAT的逻辑题，谁来解释一下逻辑

20. Whenpeople predict that certain result will not take place unless a certain actionis taken, they believe that they have learned that the prediction is correctwhen the action is taken and the result occurs. On reflection, however, it oftenbecomes clear that the result admits of more than one interpretation. Which of the following, if true, bestsupports the claims above? (A) Judging thesuccess of an action requires specifying the goal of the action. (B) Judgingwhich action to take after a prediction is made requires knowing about other actionsthat have been successful in similar past situations. (C) Learningwhether a certain predictive strategy is good requires knowing the result usingthat strategy through several trials. (D) Distinguishinga correct prediction and effective action from an incorrect prediction andineffective action is often impossible. (E)Making a successful prediction requires knowing the facts about the context ofthat prediction. 正确答案是D，我排除法做出来的，ABCE都有问题，但D怎么就对了，不懂。

Answer 1

举个例子:
有人说成绩高是因为努力，所以如果谁很努力而且成绩很好，人们就可以理解。但是实际上，努力只是成绩好的一个因素。
D的意思就是成绩好和学习努力之间没有充分必要关系，所以不可能分辨哪个是哪个的原因或结果。希望你理解。可以追问。