天山-3-3

soaring

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?

Whether farmers who tried the modified cotton seed had ever tried growing other crops from genetically modified seed.

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

Whether for most farms who grow cotton it is their primary crop

Whether the farmers who have tried the modified speed planted as many acres of cotton, on average, as farmers using the ordinary seed did.

Whether most of the farmers who tried the modified seed did so because they had previously had to use exceptionally large quantities of insecticide.

The answer is B or D?

请帮忙分析一下

judydongxueni

个人认为是b呀。

因为题目是想判断基因改造后的棉花和原来的棉花哪个更有经济效益。

b项如果可以知道的话：

如果前者和后者用的杀虫剂不一样那就意味着虽然用的量一样但是前者可以比后者省很多成本。

D项个人认为应该是无关选项，因为economically暗含了平均而不是总量的含义，而且种的多少似乎和基因改造也没有关系呀。

蓝夕叶子

http://forum.chasedream.com/dispbbs.asp?BoardID=24&ID=83238

soaring

以下是引用蓝夕叶子在2005-5-11 0:47:00的发言：

http://forum.chasedream.com/dispbbs.asp?BoardID=24&ID=83238

都说得挺有道理。。。