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 pes-

ticide, 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 vari-

eties in the past.

请问E为什么不可以？是因为E将非基因现在与以前比，从而无关么？那么D的产量问题到底是无关还是指出了这个Practice的一个wealness?

谢谢！

答案是不是D啊

"their use is likely to become the norm"  这个argument的conclusion

但是它仅从cost,less pesticide(包括人们喜欢less pesticide)两方面就推出这个结论     显然还需要产量啊

我认为D就是这个从产量出发评价这个argument  

E的话 讲的内容 out of scope

答案是D

谢谢樓上的解释：）