[求助]请教OG-61题

The recent dicline in the value of the dollar was triggered by a prediction of slower economic growth in the coming year . But that prediction would not have adversely affected the dollar had it not been for the government 's huge budget deficit , which must therefore be decreased to prevent future currency declines .

Which of the following ,if ture ,would most seriously weaken the conclusion about how to prevent future currency declines?

A: The government has made little attempt to reduce the budget dificit .

B:The budget dificit has not caused a slowdown in economic growth .

C:The value of the dollar diclined several times in the year prior to the recent prediction of slower economic growth .

D:Before there was a large budget deficit,predictions of slower economic growth frequently caused diclines in the dollar's value.

E:When there is a large budget dificit, other events in addition to predictions of slower economic growth sometimes trigger declines in currency value.

答案是D

请指教

原文的逻辑，是B导致了C, 所以不是A导致了C. 用了他因削弱。

答案的逻辑，在B存在以前，都是A导致了C. 也就是非B也会有C，排除了他因。所以削弱。