求教GWD12 Q38

beijin111

Outbreaks of Rift Valley fever occur irregularly in East Africa, several years apart.  When outbreaks do occur, they kill thousands of cattle.  A livestock vaccine against the disease exists but is rarely used.  It is too expensive for farmers to use routinely, and since it is not effective until a month after vaccination, administering it after an outbreak begins helps very little.  Nevertheless, experts predict that use of the vaccine will increase significantly within the next few years.
Which of the following, if true, provides the strongest justification for the experts’ prediction?
A.    Rift Valley fever is spread by mosquitoes, but each outbreak is so widespread that it is impractical to control it by using insecticides.
B.    When an outbreak of Rift Valley fever occurs, unaffected countries often refuse to import livestock from the countries affected by the outbreak.
C.    It would take less than a month for producers of the vaccine to adjust their production operations to cope with a large increase in demand.
D.    Many cattle farmers in East Africa are nomadic or live in remote villages, and such farmers, who have little access to modern veterinary medicine, are particularly hard hit by outbreaks of Rift Valley fever.
E.    Recently published research has shown that certain identifiable climatic conditions are almost invariably followed, within two to five months, by an outbreak of Rift Valley fever.

答案E，请问B为什么不对？当那些未受影响的国家拒绝购买感染的牲口时，农民没有收入，这与较贵的疫苗价格相比，更不划算，所以会迫使农民们给牲口打针。相反的，E选项反而与题干中的in the next few years 时间范围有所不对称,因为recently 的研究很有可能在几个月后就被推翻了，无法保证未来几年的情况。

实在想不通，向各位请教~

Areak

如果B对，那么就不是未来几年疫苗会畅销了，B对的话，疫苗应该一直畅销才对，这就导致B有一个驳斥原文中事实内容的毛病
E没有这个毛病，recently的研究是指对未来的预测，和题目中nevertheless后面专家的prediction吻合。
希望对你有帮助

ripplesyi

这题关键在于砖家预测以后的用量会大增。从以前没人用疫苗到大增之间缺一个条件，E就是那个条件。B的话，从前和将来是一样的。如果B改成邻国最近版了这个法令倒是有可能对的。个人意见。

beijin111

嗯，懂了，B关键是不能保证转变，谢谢各位