有道题天山与GWD不一样~~~请帮忙

pandaeyes

Q3:

Scientists have made genetic modifications to cotton to increase its resistance to insect

pests. According to farmers’ reports, the amount of insecticide needed per acre to control

insect pests was only slightly lower for those who tried the modified seed than for those

who did not. Therefore, since the modified seed costs more than ordinary seed without

producing yields of higher market value, switching to the modified seed would be

unlikely to benefit most cotton farmers economically.

Which of the following would it be most useful to know in order to evaluate the argument?

A. Whether farmers who tried the modified cotton seed had ever tried growing other

crops from genetically modified seed

B. Whether the insecticides typically used on ordinary cotton tend to be more

expensive than insecticides typically used on other crops

C. Whether for most farmers who grow cotton it is their primary crop

D. Whether the farmers who have tried the modified seed planted as many acres of

cotton, on average, as farmers using the ordinary seed did（题中已经表明是比较per acre啊。。。GWD答案）

E. Whether most of the farmers who tried the modified seed did so because they had

previously had to use exceptionally large quantities of insecticide

Answer:

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s7s7

这道题D错，B对

这题无非就是在评估：基因修饰的种子是否有更大的经济收益

经济收益= 总产出
                – 总投入

在总投入中，有两部分，种子投入和农药投入

基因修饰的种子成本投入显然高，但如果基因修饰的种子使用的农药很便宜，使用数量也不大，就会使最后的经济收益增加。