求解，这道题，很有难度？

koyikoyi

Plantings of cotton bioenginineered to produce its own insecticide against bollworms,a major cause of crop failure,sustained little bollworm damage until this year.This year the plantings are being seriously damaged by bollworms.Bollworms,however,are not necessarily developing resistance to the cotton's insecticede.Bollworms breed on corn,and last year more corn than usual was planted throughout cotton-frowing regions.So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms
In evaluating the argument,which of the followin gwould it be most useful to establish?
(A)Whether corn could be bioengineered to produce the insecticide
(B)Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year
(C)Whether orher crops that have been bioengineered to produce their own insecticide successfully resist the pests against which the insecticide was to protect them
(D)Whether plantings fo bioengineered cotton are frequently damaged by insect pests orher than bollworms
(E)Whether there are insecticides that can be used against bollworms that have developed resistance to the insecticede produced by the bioengineered cotton

Jackjokes

Plantings of cotton bioengineered to produce its own insecticide against bollworms, a major cause of crop failure, sustained little bollworm damage until this year. This year the plantings are being seriously damaged by bollworms (Background facts).
Bollworms, however, are not necessarily developing resistance to the cotton’s insecticide (opinion).
Bollworms breed on corn, and last year more corn than usual was planted throughout cotton-growing regions.
So
it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

Inevaluating the argument, which of the following would be most useful to establish?

So the
conclusion
is: It is likely that the cotton is damaged by bollworms breeding on corn. The
premises: 1) boll worms breed on corn; and 2) more corn than usual was planted in the cotton-growing regions.

If you look at the argument, it hinges on the assumption that the bollworms eating cotton come from the corn field.


To find the correct answer for an evaluation question, you simply answer Yes or No to the evaluation question, and then see the effects on the conclusion.

B) Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year.

If Yes, then cotton crops are heavily damaged by bollworms. It agrees with the conclusion that bollworms from corn field eat cotton. The conclusion holds.
If No, then we have a problem with the conclusion. If cotton without bio-inseticide does not suffer from unusual damages from bollworm, there might not be HUGE amount of bollworm coming from the corn field. Then the heavy damage to bio-engineered cotton is caused by the bollworm breeding within these bio-engineered cotton. Thus, the conclusion falls apart.

chaomat1988

这题其实可以这样理解。cotton有两种不同类型，一种是会产生杀虫剂的，这杀虫剂能杀死b，即文中提到的bioengineered cotton。另一种是不产生能杀死b的杀虫剂的cotton。结论是，因为b吃玉米，所以今年玉米多了，b就多了，cotton们就毁的很严重。
A是说玉米能搞杀虫剂么？无关吧！
B说其他cotton是不是死的很惨？Yes的话，特殊cotton即使b再多都不会死，成了个不变量，而总体的cotton死的很惨，所以如果其他cotton死的惨，结论就成立了。反之No就不成立。
C说其他玉米blahblah……无关
D说特殊cotton会不会被别的害虫吃掉？与结论要探讨的是否因为b的增多而导致cotton死的惨无关
E是说特殊cotton有没产生某种杀虫剂能对付b的？无关