Quote:
Organic farmers are looking for non-chemical methods to rid their crops of pests. Giving crops a slight electric shock has no ill effect on crops but rids them of caterpillars. This method should be employed by organic farmers all over the country.
Which of the following, if true, most strongly supports the view that it would not be advisable to try to eradicate agricultural pests with the method mentioned above?
A. Most species of caterpillar are subject to some natural predators.
B. Many agricultural pests do not go through a caterpillar stage.
C. This method also kills insects that are agriculturally beneficial.
D. Since caterpillars of different species appear at different times of the year, several shocks would be necessary.
E. No large-scale production facilities exist today for the product that electrifies crops.
ARGUMENT
[con] farmers should use electric shocks to get rid of pests;
[prem] because such shocks have no ill effect on crops;
[prem] also, because it is a non-chemical method;
[asum] shocks that have effect on pests, but not on crops, must be beneficial overall.
WEAKEN
A. "some preds…" doesn't weaken, irev;
B. "many pests don't go through a caterpillar stage", what about those that do? irev;
D. "several shocks would be necessary" we don't know how much shocks the crops could withstand, irev;
E. "no facilities exist today for the product" but it could exist tomorrow… irev;
Answer (C): shocks kills stuff that is beneficial to crops, this weakens the premise.