OFFICIAL EXPLANATION
A new advertisement is hanging in many of the East Coast subway stations. The poster proclaims: "Let the new biological pesticide containing micro-organisms be your new best friend! Because it's used by 4 out of every 5 florists, you can be sure that this product will answer your pesticide needs."
Which of the following, if true, most seriously undermines the advertisement's argument?(A) Though an efficient pesticide on the East Coast, the new biological pesticide has yet to undergo satisfactory experimentation in other areas.
Incorrect.
To solve this Conclusion Weakening question, first break down the argument. The first sentence is a premise providing factual data. The second sentence begins with a reason conjunction (because) so it's first part is a premise and its last part is the conclusion:
Premise A: new ads have been posted in the East Coast subway stations
+
Premise B: 4 out of 5 florists use the pesticide
=
Chairperson's claim: the pesticide is really good
Possible assumption: the florists objectively chose to use the pesticide
Weakening Data: ?
You are asked to find the answer choice that most weakens the advertisement's conclusion that people living on the East Coast should use the new biological pesticide, based on the premise that 4 out of every 5 florists chose it. The correct answer could be one that exposes the argument's assumption.
As the new pesticide is being offered to buyers on the East Coast, its effect under the conditions of other areas is irrelevant and neither weakens nor strengthens the conclusion. Our task is to weaken the conclusion that for people in the East Coast this pesticide is great.(B) The company promoting the new biological pesticide sent free samples of it to all florists in the urban centers of the East Coast.
This answer choice undermines the assumption that florists chose the new pesticide objectively for its merits and quality, not because they received free samples. Once this is revealed to be incorrect, the conclusion that the pesticide should be regarded as really good because of this is weakened.(C) Two years ago, most florists were using a chemical pesticide that was popular at the time while two years prior to that, another brand of chemical pesticide was considered the norm.
Incorrect.
To solve this Conclusion Weakening question, first break down the argument. The first sentence is a premise providing factual data. The second sentence begins with a reason conjunction (because) so it's first part is a premise and its last part is the conclusion:
Premise A: new ads have been posted in the East Coast subway stations
+
Premise B: 4 out of 5 florists use the pesticide
=
Chairperson's claim: the pesticide is really good
Possible assumption: the florists objectively chose to use the pesticide
Weakening Data: ?
You are asked to find the answer choice that most weakens the advertisement's conclusion that people living on the East Coast should use the new biological pesticide, based on the premise that 4 out of every 5 florists chose it. The correct answer could be one that exposes the argument's assumption.
The florists' move from one product to another is not enough on its own to weaken the conclusion as it does not necessarily discredit them. Their changing of products may have been motivated by technological advancement, for instance.(D) The Nursery Newsweek, published at the time of the advertisement, called on florists to move from chemical pesticides to biological ones, elaborating on the latter's advantages.
Incorrect.
This answer choice provides information that supports the advertisement's claim that the new pesticide is great. The publication described in this answer choice may have influenced the florists, but since this influence is based on the advantages of the biological pesticide, and since the ad promotes biological pesticide, it can only serve to strengthen the conclusion. You are required to weaken it.(E) Pesticides are needed more in nurseries than in florist shops, where plants and flowers are usually held for short periods of time.
Incorrect.
This answer choice neither weakens nor strengthens the advertisement's claim. The fact that flowers are kept in florist shops for shorter spans of time than in nurseries does not change the fact that pesticides are needed in florist shops. Therefore, this answer choice doesn't really weaken the conclusion a great deal.