Self-study
Support Recent studies have demonstrated that smokers are more likely than nonsmokers to develop heart disease. █████ ███████ ████ ███████████ ████ ███████ ███ ████ ██████ ████ ██████ ██ █████ ███████████ ██████████ ██████████ ████ ██████ ████████ ███████████ █████████ ██ ███ ███████ ██ ██ █ █████ ██ █████ ████████ █████ ██ █ ████████ ███████████ ███████ ████████ ███████████ █████████ ███ ███ ███████████ ██ █████ ████████
Summarize Argument
The author concludes that there’s a positive correlation between drinking caffeinated beverages and the development of heart disease. This is based on the fact that studies show there’s a correlation between smoking and heart disease, and a correlation between smoking and drinking caffeinated beverages.
Identify and Describe Flaw
Even if A is positively correlated with B, and A is also positively correlated with C, this doesn’t imply that B is correlated with C.
Here, drinking caffeinated beverages might have no correlation or even a negative correlation with heart disease. Even if smokers are more likely to drink caffeine than the average person, and more likely to have heart disease, the ones who drink caffeine might not be the ones with heart disease. The caffeine-drinkers might be less likely to have heart disease among the smokers.
19.
The argument's reasoning is most ██████████ ██ █████████ ██ ███ ███████ ████ ███ ████████ █████ ██ ████ ████ ███████ ███ ███████████ ████
a
smokers who drink ███████████ █████████ ███ ████ ██████ ██ ███████ █████ ███████ ████ ███ ███████ ███ ██ ███ █████ ███████████ █████████
If the smokers who drink caffeinated beverages are less likely to develop heart disease than the ones who don’t drink such beverages, this is evidence there’s actually a negative correlation between drinking caffeinated beverages and heart disease among the people who smoke.
b
something else, such ██ ███████ ███ ███████ ███ ██ █ ████ █████████ ██████ ██ ███ ███████████ ██ █████ ███████ ████ ███ ███ ███████ █████ ██ ███ ████████
The argument doesn’t concern what causes heart disease. The author is simply trying to establish a correlation on the basis of related correlations. But the author doesn’t assume that anything is the cause of something else.
c
drinking caffeinated beverages ██ ████ ████████ ██████████ ████ ███ ███████████ ██ █████ ███████ ████ ██ ███████
This possibility doesn’t help show why caffeinated beverages might not be positively correlated with heart disease. If anything, it does the opposite, suggesting that there might be a positive correlation between caffeinated beverages and heart disease.
d
it is only █████ ██████ ███ ████ █ ██████████ ██████████████ ██ █████ ███████ ████ ████████ ███████████ ██ ██████████ ██████████ ████ ███ ███████████ ██ █████ ███████
(D) might show that genetic factors play a causal role in heart disease and undermine a hypothesis that caffeine consumption causes heart disease. But (D) presents evidence of a positive correlation between caffeine and heart disease, which supports the author’s conclusion.
e
there is a ██████ █████ ██ ████ ███ ███████████ ██ █████ ███████ ███ █████████ ████ ██ ████████ ███████████ █████████ ███ ███████
The existence of a common cause doesn’t undermine the possibility of a positive correlation between heart disease and caffeinated beverages. If anything, it supports the existence of a correlation by explaining why they might be correlated.