fozzzy wrote:
The sustained massive use of pesticides in farming has two effects that are especially pernicious. First, it often kills off the pests' natural enemies in the area. Second, it often unintentionally gives rise to insecticide-resistant pests, since those insects that survive a particular insecticide will be the ones most resistant to it, and they are the ones left to breed.
From the passage above, it can be properly inferred that the effectiveness of the sustained massive use of pesticides can be extended by doing which of the following, assuming that each is a realistic possibility?
(A) Using only chemically stable insecticides
(B) Periodically switching the type of insecticide used
(C) Gradually increasing the quantities of pesticides used
(D) Leaving a few fields fallow every year
(E) Breeding higher-yielding varieties of cropplants
CR07612
Premises:
The sustained massive use of pesticides in farming has two effects bad effects:
it often kills off the pests' natural enemies
...
Statistics : Posted by KarishmaB • on 12 May 2013, 22:59 • Replies 11 • Views 50241






