A certain eye infection has been linked to exposure to a certain type

Question

A certain eye infection has been linked to exposure to high-salinity sea water. While not dangerous, these infections are painful and often unnoticeable, at least to those who contract them. Over 80% of children ages 4-14 who bathed in a particular sea called "The White Sea" have contracted the infection in varying levels of severity. Although bathing in "The White Sea" does not always lead to a contraction of the infection, the only way to completely avoid the infection is to refrain from bathing in "The White Sea" and other Sea waters with similar level of salinity altogether.

Which of the following indicates a flaw in the author’s reasoning?

Which of the following indicates a flaw in the author’s reasoning?

A. It relies on evidence about a specific place to make a recommendation about an entire class of such places.
B. It assumes that one possible cause of a condition is the only cause of that condition.
C. It assumes to be true what it sets out to prove.
D. It makes a generalization based on one segment of the population.
E. It contradicts itself by proclaiming a condition to be not dangerous and then offering a recommendation to avoid that condition.

Zarrolou · Accepted Answer

This is tough as almost all options reflect part of the reasoning, however only one is flawed.

Which of the following indicates a flaw in the author’s reasoning?

A) It relies on evidence about a specific place to make a recommendation about an entire class of such places. 
This reflect the reasoning  "Over 80% of children ages 4-14 who bathed in a particular sea called "The White Sea"" =>avoid all Sea waters.
This is a legit reasoning, as the infection is linked with high-salinity sea water, so this recommendation makes sense.

B) It assumes that one possible cause of a condition is the only cause of that condition. 
IMO CORRECT. The first line states:  "A certain eye infection  has been linked  to exposure to a certain type of high-salinity sea water"  => " the only way  to completely avoid the infection is to refrain from bathing in "The White Sea" and other Sea waters altogether.".
We know that the infection has been linked to water, but could be linked to other factors as well, we don't know. But the passage excludes this possibility by stating that the ONLY way to avoid the infection is to refrain from sea water. This is a flawed reasoning.

C) It assumes to be true what it sets out to prove. 
This is simply not the case.

D) It makes a generalization based on one segment of the population. 
This reflects the line  "Over 80% of children ages 4-14 who bathed in a particular sea called "The White Sea" have contracted the infection in varying levels of severity." . However the text does not say " because  the children have contracted the infection everybody should avoid the sea water". The text does not generalize in such way.

E) It contradicts itself by proclaiming a condition to be not dangerous and then offering a recommendation to avoid that condition. 
It's true that the passage says that the infection is not dangerous, but it says that is painful; so offering a recommendation to avoid it is not a flawed reasoning.

fameatop · Answer

A certain eye infection has been linked to exposure to a certain type of high-salinity sea water. While not dangerous, these infections are painful and often unnoticeable, at least to those who contract them. Over 80% of children ages 4-14 who bathed in a particular sea called "The White Sea" have contracted the infection in varying levels of severity. Although bathing in "The White Sea" does not always lead to a contraction of the infection, the only way to completely avoid the infection is to refrain from bathing in "The White Sea" and other Sea waters altogether.
 Premise- Infection is linked to bathing in  high-salinity  sea water
Premise- Infection is also seen in case of bathing in  White Sea  
Assumption- (As per 1st premise, we can safely assume that the WHITE SEA water is Highly saline)
Conclusion - The only way to avoid the infection is to refrain from bathing in "The White Sea" and other  Sea waters  altogether. 
Flaw- Not all the sea waters are SALINE. 
Which of the following indicates a flaw in the author’s reasoning?
A) It relies on evidence about a specific place to make a recommendation about an entire class of such places.  - Absolutely Correct 
B) It assumes that one possible cause of a condition is the only cause of that condition.  - The conclusion does not discusses about the different cause of a condition. Incorrect 
C) It assumes to be true what it sets out to prove. - Absolute incorrect
D) It makes a generalization based on one segment of the population. - very close but Incorrect 
E) It contradicts itself by proclaiming a condition to be not dangerous and then offering a recommendation to avoid that condition. - Straight Incorrect

blueseas · Answer

hi,

IMO B.

PREMISE: A certain eye infection has been linked to exposure to a certain type of high-salinity sea water.
PREMISE:Over 80% of children ages 4-14 who bathed in a particular sea called "The White Sea" have contracted the infection in varying levels of severity

CONCLUSION:the only way to completely avoid the infection is to refrain from bathing in "The White Sea" and other Sea waters altogether.
MEANS THE ONLY WAY TO AVOID THE INFECTION IS TO AVOID SEA BATHING

It is also stated that: Although bathing in "The White Sea" does not always lead to a contraction of the infection===>but still the author is concluding that the only cause of infection is sea bathing.

Authors flawed assumption is exposure to certain type of sea water can be avoided....by ONLY avoiding sea bathing in any sea.
but there may be other possibility that people might get exposed to that sea water in cases  such as BOATING in sea .....
so author is actually assuming one of the possible cause to be the only cause.
hence B.

rukna · Answer

OFFICIAL EXPLANATION:

The question stem asks us to find a flaw in reasoning. In this question the first step is to identify the conclusion and determine whether we can find a recognizable flaw. The arguments conclusion is that “the only way to avoid contracting the eye infection is to stay away from all the sea waters including “The White Sea”. The type of reasoning discussed in the passage is a cause and effect reasoning. The author is assuming that the cause for contracting eye infection is only bathing in sea waters; this is exactly the flaw in the argument. If we do the POE then it becomes really difficult to prove that an answer choice is incorrect. In such question we should be beware of answer choice that just discusses only a part of the argument or just state what the author is doing, but the answer is not telling us what the flaw is. To test whether a choice is incorrect we can try to change the argument so that it addresses the flaw mentioned in a choice. If the conclusion still remains flawed the answer choice is incorrect. However, it is much easier in this case to find out which answer choice is correct.

A. This choice is just telling what the author is doing to prove his/ her point.

B. Correct.  This is the correct answer choice that states the flaw in the cause and effect reasoning.

C. The author is not assuming what he sets out to prove. As with answer choice (A) the argument does this but this is not a flaw in the reasoning.

D. As with (A) this choice is also just telling what the author is doing to prove his/ her point. Hence, this is not a flaw.

E. Same as other incorrect answer choices, this is not the flaw in the argument.

sashankmvv1234 · Answer

KarishmaB

could you let me know why A is incorrect? The author said infectiion is caused to certain type of high salinity sea and then cited the high sea example. Based on this how can he conclude that to avoide infection avoid white sea and "other seas"? How do we know the salinity of other seas? What is the guarantee that other seas are "high saline" seas that author is referrring above? also isn't the representing population too small? based on teenagers the author is saying to avoid the seas..

okHedwig · Answer

I got confused between A & B, please tell me why A is incorrect as A is also givng a flaw if I think like this: eye infection is linked to exposure to a certain type of high-salinity, so maybe the white sea is having that high salinity level while all other seas might not - then him relying on evidence about a specific place to make a recommendation about an entire class of such places would be the flaw right? 
Please guide me how to choose between A & B in such case. Thanks!!

Bunuel · Answer

Official Solution:

A certain eye infection has been linked to exposure to high-salinity sea water. While not dangerous, these infections are painful and often unnoticeable, at least to those who contract them. Over 80% of children ages 4-14 who bathed in a particular sea called "The White Sea" have contracted the infection in varying levels of severity. Although bathing in "The White Sea" does not always lead to a contraction of the infection, the only way to completely avoid the infection is to refrain from bathing in "The White Sea" and other Sea waters with similar level of salinity altogether.
 
Which of the following indicates a flaw in the author’s reasoning?

A. It relies on evidence about a specific place to make a recommendation about an entire class of such places.
B. It assumes that one possible cause of a condition is the only cause of that condition.
C. It assumes to be true what it sets out to prove.
D. It makes a generalization based on one segment of the population.
E. It contradicts itself by proclaiming a condition to be not dangerous and then offering a recommendation to avoid that condition.

The conclusion of the author is that “the only way to completely avoid the infection is to refrain from bathing in "The White Sea" and other Sea waters with similar levels of salinity altogether”. There are two  extreme  words in the conclusion that are particularly susceptible to flawed reasoning:
  
A. “the  only  way”
   
B. “ completely  avoid”
  
Flaw in point A:

There may be some other way to avoid the infection (some people who bathed in the “White Sea” did not get infected), but the author assumes refraining from bathing in the “White Sea” and other high-salinity seas is the  only  way.

(This flaw is not depicted in any of the answer choices though.)
 
Flaw in point B:

What is required to be done to  completely  avoid the infection:
 
a. Refrain from bathing particularly in “White Sea”.
   
b. Refrain from bathing generally in a high-salinity sea water since it is known that “high-salinity sea water” is linked to the infection ( ref. first sentence of the passage).
   
c. Any other reason that might cause the infection.
  
A. This choice is just telling what the author is doing to prove his/ her point. This is not a generalization flaw as one might think. In the argument, the author has included 2 (a and b) of the 3 points stated under “Flaw in point B” above. Including point b basically shows a positive aspect of the author's conclusion - that he extended his observation to a larger field.
 
 B. CORRECT.  This is the correct answer choice that states the flaw in the cause and effect reasoning. This option shows that point c in “Flaw in point B” was missed out by the author.
 
C. The author is not assuming what he sets out to prove. As with answer choice (A) the argument does this but this is not a flaw in the reasoning.
 
D. As with (A) this choice is also just telling what the author is doing to prove his/ her point. Hence, this is not a flaw.
 
E. Same as other incorrect answer choices, this is not the flaw in the argument.

Answer: B

A certain eye infection has been linked to exposure to a certain type

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A certain eye infection has been linked to exposure to a certain type

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