Asthma, a chronic breathing disorder, is significantly more common

We are looking for a statement that if true would negate the argument that exposure to swimming pool water is the reason swimmers have higher incidence of asthma than other athletes. Well, this argument is a classic correlation-causation error. If we can point out that the correlation does not imply causation in this case, e.g., by showing that something else causes the correlation, we will weaken that argument. Answer choice D explains why swimmers have relatively high incidence of asthma - asthmatic children tended to train to become swimmers because their doctors advised them to.

sir i want to ask that the case is of people : adult competitive swimmers. but there is no surety the children sent to pool will become adult competitive swimmer they can go for few months and leave as part of medial procedure .i got D by POE but have doubts

Dear oishik2910,

I'm happy to respond.

With all due respect, I don't understand what you are asking here. I am going to ask you to rephrase your question more clearly. Please be very careful about spelling mistakes (e.g. "medial" ==> "medical") that can make what you say harder to understand. Also, you are using the word "surety" in a somewhat infrequently used sense, which adds further to making this difficult to understand. Please be more careful phrasing your question. Thank you.

Mike

mike
sir

the reason we have picked choice D because it shows that why so many people with asthma wound up in competitive swimming. It's not that being in the pool causes the asthma (the naive, rash conclusion); instead, the people who already had asthma were sent to the pool
but my doubt is
children are sent to swimming pool as a part of medical procedure but they may or may not become competitive swimmer : for instance
50 children were sent to swimming for 3 months to bring their asthma out but none of them became a competitive swimmer

Dear oishik2910,

Thank you for clarifying. I am happy to respond.

Think about how this plays out.

First of all, asthma is a chronic condition: it has treatments but no known cure. That is real world knowledge you need to know. Therefore, the children would not have been sent to the pool for 3 months only: they would have been in the pool for much of the time they were growing up, if the parents really thought this would help their chronic condition.

Next, of course the doctor would have told the parents: the pool will help your child's asthma. Would the children have known this? Or in the child's view, would these trips to the pool have been just for fun? Of course, to some extent, it would depend on the child's age at the onset of asthma: younger children might be less aware of the true purpose and more likely to understand the trip solely in terms of their experience of fun.

Keep in mind, too, that by and large, children love to swim and play in a pool. In some parts of the US, pool parties are a common birthday party time, especially during warm months in hot areas. Kids love pools. Even children who are initial timid or who don't know how to swim, once they have been trained and acclimated often have a blast. In my estimation, it's a minority of children who actively do not like to be in the pool. The many incentives of going to the pool multiply as children reach teenager years, but we will leave that aside. All this is to say that what started as trips to the pool for medical reasons may quickly involve into something the child wants to do, a vital part of her play and her social life.

So, we have a large population of children, going to the pool frequently during their entire childhood, and most likely enjoying it. Of course, not all of them will become competitive swimmers, but this sounds like a plausible backstory for anyone who does become a competitive swimmer. We certainly would not expect a competitive swimmer to say, "I never was in the pool much as a child."

All the argument is suggesting is that people who spend most of their childhood going to the pool are more likely to become competitive swimmers than folks who didn't go to the pool much as children.

Does all this make sense?
Mike

This question is not hard to solve but took me more than 1m30s to solve it. To speed up, I personally think it's more important to practice with more precision and sensitivity to logic gaps. In this case because there is high incidence of asthma among swimmers doesn't mean it's caused by the sport. What if more people with Asthma will choose swim over other competitive sports?

Stimuli:
Premise 1 - Asthma is more common among swimmers than among other competitive sports
Premise 2 - chlorine is lung irritant and swimming pool water is chlorinated
Conclusion - too rash to conclude chlorine contributes to high incidence of Asthma among swimmers
- this question is not hard to solve but it took me more than 1m30s to solve it. Spee

Question: look for another assumption

Answers
A) this didn't explain within competitive sports, why swimming is different from others. so irrelevant
B) this strengthen the effect Chlorine has on high incidence of Asthma, so incorrect
C) same as A, incorrect
D) this explains more children with Asthma will participate in competitive swimming than other sports, weaken the Chlorine's effect
E) same as A, incorrect

Hi mikemcgarry, AjiteshArun, GMATNinja, HanoiGMATtutor and other verbal experts,

This question really got me as I was so confused why people with asthma can become a professional swimmer that I could not see the whole picture clearly. (I guess The Big Ban Theory it to be blame--it is hard to imagine Leonard Hofstadter as a competitive swimmer, just kidding.) However, I have some doubts about the options (D) and (A) and hope you could help clarify the doubts.

Regarding the option (D), how is the phrase "until a few years ago" playing here? If this phrase were removed from the option (D), would the option still be a winner? I suppose so but I am not very sure.

Regarding the option (A), if the option were revised to "young people who have asthma are less likely to become competitive athletes than are young people without asthma," would this kind of provide evidence to the hypothesis which the author hopes to reject? (The hypothesis is that frequent exposure to chlorine is the explanation of the high incidence of asthma among adult competitive swimmers.) I suppose so and my reasoning is the following: since young people with asthma are less likely to become swimmers, most swimmers might develop asthma during adulthood, in which scenario the exposure to chlorine in the pool could be more likely to be the cause. But, I am not very sure about my reasoning and hope to hear your ideas on it.

Thanks in advance for your time and response!

Hi GraceSCKao,

Good question. I think that the phrase "until a few years ago" is quite important, though it's probably not essential. The question is about adult competitive swimmers, so we can expect that something that was recommended to children with asthma until a few years ago would affect adults today (today's adults were children at that earlier time). Now, without that phrase, option D would look like this:

1. physicians routinely recommended competitive swimming to children with asthma

There's a (possible) problem with this. We can't say anything about when in the past physicians recommended this. Did they recommend swimming to children with asthma long, long ago? Or were they still doing it when it could affect what we see in adults today?

2. until a few years ago, physicians routinely recommended competitive swimming to children with asthma

This is option D. With the modifier in place, we know that the practice of recommending swimming to children with asthma was, in fact, still being followed "until a few years ago". "A few years ago" can reasonably be considered a time when the practice of recommending swimming to children with asthma could affect today's adults.

Understand the Passage

Asthma, a chronic breathing disorder, is significantly more common today among adult competitive swimmers than it is among competitive athletes who specialize in other sports.This statement compares the incidence of asthma between competitive swimmers and other competitive athletes. The incidence of asthma is significantly higher in competitive swimmers than it is in other competitive athletes.

Although chlorine is now known to be a lung irritant and swimming pool water is generally chlorinated. If we read this part in context of the above statement, we’ll understand that this statement seems to provide a reason for the first statement. The reason for higher incidence of asthma among competitive swimmers could be the presence of chlorine in swimming pools.

However, since this clause forms a part of ‘Although’, we can expect the following clause to say something in the opposite direction.

it would be rash to assume that frequent exposure to chlorine is the explanation of the high incidence of asthma among these swimmers, since __________. As expected, this part says (something opposite) that the presence of chlorine in swimming pools should not be assumed to be the cause of higher incidence of asthma among these swimmers. This part ends with ‘since’. So, we need to find a reason why the presence of chlorine shouldn’t be assumed to be the cause.

Predict an Answer

Any alternate cause for the higher incidence of asthma in competitive swimmers would be an answer. Also, any option that suggests that competitive swimmers are sufficiently guarded against the harmful effects of chlorine in swimming pools will also be an answer.

Option Analysis

(A) Incorrect. The first thing to notice here is that this option talks about competitive-athlete-category as a whole. It doesn’t distinguish between competitive swimmers and other competitive athletes. Since the whole point of the passage is to explain the higher incidence of asthma among competitive swimmers vis-à-vis other competitive athletes, an option that doesn’t distinguish between these two categories of competitive athletes will always be irrelevant.

Even if we change ‘competitive athletes’ to ‘competitive athletes who are not competitive swimmers’, the option will still be incorrect. The changed option means that we don’t have a biased population of young people coming into other competitive athletics (biased here means more likely to have asthma). The option thus means that there is no reason to expect a higher than normal incidence of asthma among competitive athletes who are not swimmers. However, this option fails to give any reason for higher incidence of asthma among competitive swimmers or any reason why the presence of chlorine cannot lead to higher incidence of asthma among competitive swimmers.

Even if we change ‘competitive athletes’ to ‘competitive swimmers’, the option will still be incorrect. Rather, in this case, the negation of this option will be a possible answer.

(B) Incorrect. This option is in the opposite direction to the correct answer. If other competitive athletes are rarely exposed to chlorine and, we know that, competitive swimmers are frequently exposed to chlorine, then it seems reasonable to expect that chlorine leads to higher incidence of asthma among competitive swimmers. This expectation is opposite to the stated last line.

(C) Incorrect. For the same reason as stated in option A. This option talks about competitive-athletes-category as a whole.

(D) Correct. If physicians routinely recommended competitive swimming to children with asthma, then we can expect a higher proportion of people with asthma in competitive swimming than in other sports. Thus, this option provides an alternate reason for the higher incidence of asthma among competitive swimmers. A higher proportion of people joining competitive swimming have asthma than joining other competitive athletics. This can explain the higher incidence of asthma among competitive swimmers than among other competitive athletes. Thus, the presence of chlorine in swimming pools may not be the explanation for the higher incidence of asthma among competitive swimmers.

(E) Incorrect. Again, this option is incorrect for the reason stated in option A: it talks about the category of competitive athletes as a whole. In case no distinction is made between competitive swimming and other competitive sports, then whatever is applicable for competitive swimming must be applicable for other competitive sports too. Thus, this scenario will not give us any reason to expect a higher incidence of asthma among competitive swimmers.

If you have any doubts regarding any part of this solution, please feel free to ask.

I have doubts about D.
The stem says that chlorine is 'now' known to be a lung irritant and the doctors prescribed swimming for people with asthma 'a few years ago'. Does this mean that a few years back doctors did not know the negative effects of chlorine and thus recommended it to asthma patients? In reality, it only worsened their condition?

Please help me with this GMATNinja and other experts

Yup, you're on the right track!

We're trying to figure out why we CAN'T attribute swimmers' asthma to frequent chlorine exposure, even though we know that chlorine irritates the lungs.

(D) tells us that doctors used to tell asthmatic kids to start competitive swimming. So, the chlorine didn't CAUSE the asthma -- kids ALREADY had asthma, and then started swimming competitively. That can explain the high incidence of asthma among competitive swimmers.

(D) logically completes the passage by providing support for the author's conclusion.

I hope that helps!

­
Hi AjiteshArun KarishmaB
I have a doubt- Had option C been competitive 'swimmers' as a group have a significantly lower incidence of asthma than do people who 'specialise in other sports' 
Could I consider it as a weakener and thus a potential answer (not considering D)? 

­This would make the option conflict with the given data in the first sentence of the argument:

Asthma is significantly more common today among adult competitive swimmers than it is among competitive athletes who specialize in other sports.­

­A. This might help explain why competitive athletes in general are not especially likely to have asthma, but it does not explain why adult competitive swimmers are more likely to have asthma than other competitive athletes are.

B. This provides additional evidence that exposure to chlorine explains why adult competitive swimmers are more likely to have asthma than other competitive athletes are, so it does not cast doubt on that hypothesis.

C. A lower incidence of asthma among competitive athletes than among nonathletes does not help explain the higher incidence of asthma among adult competitive swimmers than among other competitive athletes.

D. Correct. Routinely encouraging children with asthma to take up competitive swimming would likely have made the proportion of adult competitive swimmers with asthma exceed the proportion of other competitive athletes with asthma, even if chlorine in swimming pool water never causes asthma in swimmers.

E. This might help explain why people with asthma are just as likely as other people to become competitive athletes, but it does not help explain why adult competitive swimmers are more likely to have asthma than other competitive athletes are.

The correct answer is D.

Although I understand how d is the perfect option but doesn't option D talk about children and the context of whole passage is about adult competitive swimmers?­

­In letter D, when it says "until a few years ago" how can I be sure that is the case that they still reccomend? I did not mark D because I thought "Ok, until few years ago, but maybe they don't reccomend it anymore because they now know about the chlorine problem".

Can anyone please help? Thanks!

­The passage explores why asthma is common among "adult competitive swimmers." (D) tells us that "until a few years ago, physicians routinely recommended competitive swimming to children with asthma."

Do we need to know that asthmatic children are CURRENTLY encouraged to swim? Nope -- we (perhaps callously) don't care about current children. Instead, we care about current adults. These adults used to be children, and at that time doctors recommended that they swim competitively.

In all, (D) tells us that doctors used to tell asthmatic kids to start competitive swimming. So, the chlorine didn't CAUSE the asthma -- kids ALREADY had asthma, then started swimming competitively, then grew into adult competitive swimmers.

(D) logically completes the passage by providing support for the author's conclusion.

I hope that helps!­