涛涛GWD31-9-3

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?

1. Whether farmers who tried the modified cotton seed had ever tried growing other crops from genetically modified seed
2. Whether the insecticides typically used on ordinary cotton tend to be more expensive than insecticides typically used on other crops
3. Whether for most farmers who grow cotton it is their primary crop
4. Whether the farmers who have tried the modified seed planted as many acres of cotton, on average, as farmers using the ordinary seed did
5. 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

理不出思路，请高手指教。

我倾向于B.主要看insecticide 有没有问题.

大家感兴趣的就来讨论一下吧.

D更好，已试种过转基因作物的农民最清楚这种作物有没有经济价值，若有，多种，没有，少种（平均而言），因此他们种植的量可以作为评判标准。

欢迎批评指正

应该选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

平均/acre modified seed 和ordinary seed 一样多才具有比较性

modified seed 种植密度很高，ordinary seed 平均/acre 种植很少，nsecticide差不多则说明modified seed 好。

同意！

但是Ｄ说的是as many acres啊，我认为如果能说明每亩种植cotton的密度即可，但是Ｄ说的是总的亩数，所以我当时做的时候就觉得木有答案了．

即使总的亩数多的话，只要每亩的（yields-costs）不比原来少就不经济了，所以我认为Ｄ不应该是正确答案，ＢＵＴ其他选项就更无关了．真是木有答案了

但是如果按照３楼说的那样的话，似乎可以解释得通，但是跟文中的推理又有虾米关系呢？

http://forum.chasedream.com/dispbbs.asp?boardid=24&replyid=1354869&id=83238&page=1&skin=0&Star=1

很长的讨论

个人倾向于B

我认为选E. 如果选转基因棉的农民因为特殊原因以前需要用exceptionally large quantities of pesticide来控制虫害，就说明他们的种植环境比其他农民的种植环境虫害更多。这样在选转基因棉即使虫害比其他农民只下降一点，也说明很有用。

B Whether the insecticides typically used on ordinary cotton tend to be more expensive than insecticides typically used on other crops

如果other crops改为modified cotton. B才能正确吧。