Critical Reasoning

Which of the following most logically completes the argument given?

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. Although chlorine is now known to be a lung irritant and swimming pool water is generally chlorinated, it would be rash to assume that frequent exposure to chlorine is the explanation of the high incidence of asthma among these swimmers, since __________.

A. young people who have asthma are no more likely to become competitive athletes than are young people who do not have asthma
B. competitive athletes who specialize in sports other than swimming are rarely exposed to chlorine
C. competitive athletes as a group have a significantly lower incidence of asthma than do people who do not participate in competitive athletics
D. until a few years ago, physicians routinely recommended competitive swimming to children with asthma, in the belief that this form of exercise could alleviate asthma symptoms
E. many people have asthma without knowing they have it and thus are not diagnosed with the condition until they begin engaging in very strenuous activities, such as competitive athletics

OA: D

OA talks about children with asthma whereas the question is about competitive adult swimmers. What is the assumption lying behind the logic in this option?

lionsshare wrote:Which of the following most logically completes the argument given?

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. Although chlorine is now known to be a lung irritant and swimming pool water is generally chlorinated, it would be rash to assume that frequent exposure to chlorine is the explanation of the high incidence of asthma among these swimmers, since __________.

A. young people who have asthma are no more likely to become competitive athletes than are young people who do not have asthma
B. competitive athletes who specialize in sports other than swimming are rarely exposed to chlorine
C. competitive athletes as a group have a significantly lower incidence of asthma than do people who do not participate in competitive athletics
D. until a few years ago, physicians routinely recommended competitive swimming to children with asthma, in the belief that this form of exercise could alleviate asthma symptoms
E. many people have asthma without knowing they have it and thus are not diagnosed with the condition until they begin engaging in very strenuous activities, such as competitive athletics

OA: D

OA talks about children with asthma whereas the question is about competitive adult swimmers. What is the assumption lying behind the logic in this option?

This is a classic causality argument. We know that swimmers have a higher incidence of asthma than do other types of athletes. One way to interpret this is to blame swimming for the condition. Swimming --> asthma.

However, if it isn't swimming that's causing asthma, but rather, asthma that's causing athletes to pursue swimming rather than other types of sports, (asthma ---> swimming) we'd have an alternative explanation for the correlation that would not indict chlorine as a culprit for the condition.