carcass wrote:
Nonprescription sunglasses shield the wearer's eyes from damaging ultraviolet sunlight. Squinting, however, provides protection from ultraviolet rays that is at least as good as the protection from nonprescription sunglasses. There is, therefore; no health advantage to be gained by wearing nonprescription sunglasses rather than squinting.
Which of the following, if true, most seriously weakens support for the conclusion above?
(A) Many opticians offer prescription sunglasses that not only screen out ultraviolet sunlight but also provide corrective vision.
(B) Some nonprescription sunglasses provide less protection from ultraviolet sunlight than does squinting.
(C) Squinting strains facial muscles and causes headaches and fatigue.
(D) Many people buy sunglasses because they feel that sunglasses are fashionable.
(E) Some people squint even when they are wearing sunglasses.
Identify the Question: Weaken
Deconstruct the Argument (in your own words)!
[*] Premise 1: Non-prescription sunglasses protect from UV.
[*] Premise 2: Squinting gives same protection as said sunglasses.
[*] Conclusion: Because sunglasses and squinting offer UV protection, no health benefits are present.
Pre-phrase AnswerWe are searching for an answer that says: sunglasses
are not equivalent to squinting
and/or sunglasses/squinting
offer health benefits.
Quote:
(A) Many opticians offer prescription sunglasses that not only screen out ultraviolet sunlight but also provide corrective vision.
Ok, maybe. This says sunglasses =/= squinting because it helps correct vision. We'll keep this for now, assuming that correcting vision is a health benefit...but I'm wary. Just because "
many opticians offer sunglasses with corrective vision" is a very narrow view. It's basically saying: you could possibly gain health advantages to buying non-prescription sunglasses WITH corrective vision added....but to be honest, not feeling the vibes that much on this one so let's move on.
Quote:
(B) Some nonprescription sunglasses provide less protection from ultraviolet sunlight than does squinting.
This is basically repeating the premise 2: "Squinting, however, provides protection from ultraviolet rays that is at least as good as the protection from nonprescription sunglasses." Repeating the premise does not weaken the conclusion.
Quote:
(C) Squinting strains facial muscles and causes headaches and fatigue.
I like this one. It mentions that sunglasses =/- squinting with the reasoning that squinting causes headaches, which weakens the argument that the author concluded.
Quote:
(D) Many people buy sunglasses because they feel that sunglasses are fashionable.
This tells us why people buy sunglasses but doesn't have any effect on the conclusion. I like to think of it as if I added this sentence to the above stimulus, what would that say? OK, many people wear sunglasses because it is fashionable and therefore, sunglasses offer no health benefits. Nonsense!
Quote:
(E) Some people squint even when they are wearing sunglasses.
Saying that we squint while wearing sunglasses to ATTACK the fact that there are no health benefits doesn't make sense either. If anything, this is saying that squinting and sunglasses are likely useless in protecting from UV rays.
And finally between
(A) and
(C). The stated as true fact of (C) squinting causing fatigue best weakens the argument about sunglasses and squinting being of equal health benefit.
close
20 Feb 2019, 06:24
25%
(medium)
23%
(01:40)
wrong 
