GMAT Critical Reasoning (CR) | Re: Smoking is a known cause of certain serious health problems,

Although the premises of this argument suggest only a correlation between smoking and anxiety or nervousness, the argument has a causal conclusion: it concludes that smoking causes individuals to be anxious and nervous (i.e., that A causes B). Any assumption in a causal argument must support the causal “direction” of the conclusion, that A causes B as opposed to some other explanation. Often, assumptions support a causal conclusion either by eliminating an alternate cause for the conclusion
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