GMATinsight wrote:
Is there a causal relationship between smoking and lung cancer?
(1) Research consistently shows a strong correlation between smoking and the development of lung cancer
(2) Some medical researchers support a proposed mechanism by which smoking could cause lung cancer.
Source:
OG 2025-25 Code: 700322
OFFICIAL EXPLANATIONInference(1)
Research-based evidence has consistently shown a high positive correlation between smoking and lung cancer. A strong positive correlation between two factors P and Q indicates that there is a similar pattern of variation in data for P and data for Q (the degree of similarity can vary). For example, long-term data might show that as smoking increases in a population, the data regarding the incidence of lung cancer increases in tandem. Over several years, if the data regarding smoking in a population decreases, the data for lung cancer might also decrease. In both cases, a positive correlation occurs. But such a statistical pattern, by itself, can, at best,
suggest some
association or
dependency, direct or indirect, between the two factors smoking and lung cancer. But correlation evidence, by itself, provides no proof of a causal relationship; NOT sufficient.
(2) The information provided is insufficiently specific to sustain a claim that smoking is causally related to lung cancer. What (2) indicates is a
hypothesisproposed by some researchers, but no information is provided to indicate confirmation of that hypothesis; NOT sufficient.
The correct answer is E; both statements together are still not sufficient.--
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