Pear Trees

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Pear Trees

by kaulnikhil » Fri Dec 18, 2009 11:15 am
The local agricultural official gave the fruit growers
of the District 10 Farmers' Cooperative a new
pesticide that they applied for a period of three.years
in their pear orchards in place of the pesticide they
had formerly applied' During those three years, the
Proportion of pears lost to insects was significantly
iess-than it had been during the previous three-year
period. On the basis of these results, the official
concluded that the new pesticide was more effective
than the old pesticide, at least in the short term, in
limiting the loss of certain fruit to insects'
The official's conclusion is most strongly supported
if which one of the following groups of trees did not
show a reduction in losses of fruit to insects?
(A) peach trees grown in the district that were
treated with the new pesticide instead of the
old Pesticide
(B) peach trees grown in the district that were
treated with the new pesticide in addition to
the old Pesticide
(C) Pear trees grown in the district those were
treated with the old pesticide instead of the
new pesticide
(D) pear trees grown in a neighboring district that
were treated with neither the old nor the new
pesticide
(E) pear trees grown in the district that
-were
treated with the new pesticide instead of
the old Pesticide
Source: — Critical Reasoning |

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by Testluv » Fri Dec 18, 2009 12:20 pm
First of all, the scope of the argument is pear trees and not peach trees, so we can eliminate choices A and B immediately (ie, without having to read them). We are looking to bolster the argument that it was the new pesticide that was the cause of the trees being less vulnerable to insect damage. The stem is specific here: we need to figure out how to strengthen the argument by thinking about a group of trees that are still vulnerable to insect damage. Well, if we want to strengthen the idea that the new pesticides are the thing making pear trees less vulnerable to insect damage, then a choice that shows that without the pesticides the trees are still vulnerable to insects would do the trick--that's choice C.
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