OA is D Why is A incorrect?[/img]

Hi Well..A is explicitly stated in the argument(last sentence). No need to use its contra-version against the argumnet. What's more it does not take you any where! A premise, fact can not be weakener itself. D correctly refutes the expectation of a fall in the price, since disease will eat up all the corn, there will be a shortage and prices will go up! Cheers!

Thanks ozlemg. Only that the last line of the argument says: P-> Adequate moisture is required for current crop's survival... now,my point is: Doesnt 'current crop' mean the 'standing crop' (ready to be harvested in some time)? (and since the rains are only arriving now,i.e. after pollination the yield will be less) also, P->meteorologists predict much needed rain in corn growing regions. which means the rainfall during the pollination time was not adequate. could u clarify this point? Or am i pondering too much?:)

AN24 wrote: Only that the last line of the argument says: P-> Adequate moisture is required for current crop's survival... now,my point is: Doesnt 'current crop' mean the 'standing crop' (ready to be harvested in some time)? (and since the rains are only arriving now,i.e. after pollination the yield will be less) The Option A is a factual statement that gives us some information that those corn crops that do not receive the necessary rainfall during their so-called pollination period, do not eventually turn out to produce a good harvest. But, in the problem stimulus, it no where tells you whether the crop has passed that stage of pollination or anything of that type. i hope it helps. Thanks

The post above is correct. We need to have something to weaken the conclusion. If you take the main conclusion of the argument, and you go to the OPPOSITE of that conclusion then you will weaken. The main conclusion is "price of corn futures will fall sharply today." So you are looking for an answer that indicates that the price of corn futures will not fall today. Choice D gives you a direct reason why the price will not fall. Disease will spread. Choice A requires lots of assumptions!!! Why go there? You have to assume that the corn is already past the critical stage or in the stage, etc. You do not know this. NEVER choose the answer that requires you to take additional steps. Choice D is a direct reason. So for the future...the answer choice that requires the fewest assumptions is the better choice.