GWD-24-29

Plant scientists have been able to genetically engineer vegetable seeds
        to produce crops that are highly resistant to insect damage. Although
        these seeds currently cost more than conventional seeds, their cost is likely to decline. Moreover, farmers planting them can use far less pesticide, and most consumers prefer vegetables grown with less pesticide,
        therefore, for crops for which these seeds can be developed, their use is likely to become the norm.

Which of the following would be most useful to know in evaluating the
        argument above?

A.      Whether plant scientists have developed insect-resistant seeds
        for every crop that is currently grown commercially

B.       Whether farmers typically use agricultural pesticides in larger
        amounts than is necessary to prevent crop damage.

C.      Whether plants grown from the new genetically engineered seeds
        can be kept completely free of insect damage.

D.      Whether seeds genetically engineered to produce insect-resistant
        crops generate significantly lower per acre crop yields than do
        currently used seeds.

E.       Whether most varieties of crops currently grown commercially have
        greater natural resistance to insect damage than did similar varieties in the past.

答案是D，我认为是B。D说产量，原文根本没有提到产量的事情啊。

B是一个很好的消除他因的选项，如果原来农民用的农药就多的不合理，那么现在他们用得农药少了可能是因为本来就不需要用那么多，而不是新品种的作用。消除这个他因可以支持原文，不消除就削弱

他的意思是评估，不是支持论点。

评估的意思就是对上述的结论如果说yes，就是支持，如果说no就是反对，起到一个对立评价的作用。

这个题的依据是：该改良的种子成本逐步降低，且防止农民少用农药，且消费者也喜欢没有农药的蔬菜，那么发展这个种子是有利的，未来可能会普及。

而B中农民是否大量使用农药无关啊，因为减少了农药总是好的，和你用一吨农药还是十吨没有关系。

而D中问道种子的产量，回答yes，则是说这个种子产量不行，那他的依据就有问题了，是否普及就不一定了；如果回答no，则说明产量没有影响，那肯定会普及。

另外C比较有迷惑，但是因为C是对文中已经确定的事实的怀疑，所以没有意义。评估题的意思就是前提是正确的，你为了评价结论，还需要考察其他什么信息！！