50. Crops can be traded on the futures market before they are harvested．If a poor corn harvest is predicted，prices of corn futures rise；if a bountiful corn harvest is predicted，prices of corn futures fall．This morning meteorologists are predicting much-needed rain for the corn-growing region starting tomorrow．Therefore，since adequate moisture is essential for the current crop's survival，prices of corn futures will fall sharply today．

Which of the following，if true，most weakens the argument above?

(A)  Corn that does not receive adequate moisture during its critical pollination stage will not produce a bountiful harvest．

(B)  Futures prices for corn have been fluctuating more dramatically this season than last season.

(C)  The rain that meteorologists predicted for tomorrow is expected to extend well beyond the corn-growing region．

(D)  Agriculture experts announced today that a disease that has devastated some of the corn crop will spread widely before the end of the growing season．

呵呵，大家不要误会，选项E不是答案。

只是发现选项 A  自己解释不通！

If a poor corn harvest is predicted，prices of corn futures rise；

A.Corn (...) will not produce a bountiful harvest.==>price of corn will

rise.

自己觉得 A 和 D都可以理解为 Weaken！

请各位拍砖！

weaken是要weaken结论啊, A和结论的具体性"today"并无关系;

另A是说没有足够的moisture就没有好收成, 不能跳过moisture这个条件直推price

of corn will rise

选择A中 确实无法得出 今年的harvest 的结果怎么样！

谢谢各位同学！

我个人到觉得关键是题目已经说了much-needed rain ,所以A就无关了,否则A是可

以weaken的啊

conclusion是：因为雨水好，所以价格下降。

其实只有AD会影响harvest，然而A更像是个support