[求助GWD]T-3-Q3.

louisehu

T-3-Q3.

Scientists have made genetic modifications to cotton to increase its resistance to insect pests. According to farmers’ report, 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 farms 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.

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.

为什么选B？和其他crops的 insecticide有什么关系？不理解。

louisehu

再顶一下，望牛人指点！

xcwestop

B是肯定无关选项的，我在D和E之间挣扎

zxppx

刚开始我也在D和E徘徊，但是当再次看到结论和B选项时，我知道读题的时候忽视了： ordinary cotton ，而这正是结论里面出现的！注意在前面的部分并没有出现ordinary cotton ！作者只是提到：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.但是，这里并没有指出是哪种农作物的杀虫剂，如果棉花的杀虫剂比较特殊，需要更高的价格，那么就可能会导致结论不成立！