Needgmat wrote:Scientists have modified feed corn genetically, increasing its resistance o insect pests. Farmers who tried out genetically modified corn last season applied less insecticides to their corn fields and sill got yeilds comparable to those they would have gotten with ordinary corn. ordinary corn seed, however, costs less, and what these farmers saved on insecticide rarely exceeded their extra costs for seed. Therefor, for most feed-corn farmers, switching to genetically modified seed would be unlikely to increase profits.

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

A) whether there are insect pests that sometime reduce feed-corn yields, but against which commonly used insecticides and the genetic modification are equally ineffective

B) Whether the price that farmers receive for feed corn has remained steady over the past few years

C) Whether the insecticides typically used on feed corn tend to be more expensive than insecticides typicaly used on other crops

D) Whether most of the farmers who tried the genetically modified corn last season applied more insecticide that was actually necessary

E) Whether, for most farmers who plant feed corn, it is their most profitable crop

OAD

Please explain.

Many thanks in advance.


Kavin

Conclusion: Switching to genetically modified corn is unlikely to increase profits.

Premise: Though the farmers planting genetically modified corn used less pesticide, the genetically modified corn was more expensive, and thus wiped out any costs savings they'd gotten from using less pesticide.

To the answer choices:

A) Equally ineffective? Irrelevant
B) Irrelevant. Though farmers surely care about the price of corn, this info sheds no light on whether using genetically modified corn would be more profitable than using conventional corn.
C) Other crops? Irrelevant.
D) If the farmers used more insecticide than was necessary, they could have saved more money by using even less insecticide. It's possible these additional savings would have been enough to make it more profitable to plant genetically modified corn. Looks good.
E) Irrelevant. We're comparing the profits made from planting genetically modified corn to the profits made by planting conventional corn. Where corn ranks in the profitability hierarchy of crops does not help answer this question.

Answer is D