Outbreaks
of Rift Valley fever occur irregularly in
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
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.
答案是E，就是看不出来有什么关系呀？？？
某种病要爆发，疫苗要提前一个月才能发挥作用，因此你要等病爆发了再用就没效果了。
那如果我能知道什么时候会爆发，我不就可以提前注射疫苗了嘛
E说的就是，一个”天气情况“发生的两到五个月内，这个病一定会产生。
那不就是告诉我们，我们是可以定位这个病爆发的时间么。
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