Self-study
Support A survey published in a leading medical journal in the early 1970s found that the more frequently people engaged in aerobic exercise, the lower their risk of lung disease tended to be. █████ █████ ███████ ████ █████████ █████ ████████ ██ ████ ██ ███ ████ ████ ███████ ████████ ███ █ ███████████ ██████████ ██████ ██ ████████ ███████
Summarize Argument: Phenomenon-Hypothesis
The author concludes that aerobic exercise leads to decreased risk of lung disease. Her premises are:
(1) A 1970s survey wherein the more frequently people engaged in aerobic exercise, the lower their risk of lung disease tended to be.
(2) Subsequent surveys yielded the same finding.
Identify and Describe Flaw
This is a “correlation doesn’t imply causation” flaw, where the author sees a correlation and concludes that one thing causes the other without ruling out the two alternatives hypotheses:
(1) The causal relationship could be reversed—people at lower risk of lung disease might gravitate toward aerobic exercise. Maybe healthy lungs make aerobics more fun!
(2) Some other factor could be causing the correlation—maybe something else (maybe living somewhere with good air quality?) causes people to both do aerobic exercise and be at lower risk for lung disease.
4.
The reasoning above is questionable ███████ ███ ████████
a
ignores anecdotal evidence ███ █████ ███ ██████████ ████████ ██ ██████████ ████████
There’s no reference to any anecdotal evidence at all, let alone any that would contradict the results of the scientific research. Therefore, there’s no support for the claim that the author is ignoring any such evidence.
b
considers only surveys █████████ ██ ███ ██████████ ███████ ███████
The stimulus doesn’t state that all the surveys the author considered were published in the same medical journal, so (B) could be factually inaccurate. Furthermore, we have no reason to believe that it would be a problem to only consider surveys published in one medical journal.
c
concludes merely from ███ ████ ████ ███ ██████ ███ ██████████ ████ ███ ██████ ███ █████
This describes the author’s cookie-cutter “correlation proves causation” flaw: based solely on a correlation (frequent aerobic exercise correlates with decreased lung disease risk), the author concludes a specific causation (aerobic exercise causes decreased lung disease risk).
d
presumes, without providing ██████████████ ████ ██████ ███ ████ ███ ████ ████ ███████ ██ ██ ████ ██████
The stimulus does not presume that anyone who doesn’t have lung disease is in good health. Rather, it states that lowered risk of lung disease is one significant benefit to a person’s health—a statement that is true whether or not that person is healthy in other respects.
e
fails to consider ████ ████ ██████████ ███████ ████████ ███ ████ ████ ██████████ ██████ ██ ████████ ██████
The author does not fail to consider the potential benefits of infrequent aerobic exercise; in fact, the conclusion makes a blanket statement regarding the purported health effects of aerobic exercise, regardless of frequency.