Critical Reasoning (CR) | Prolonged exposure to sulfur fumes permanently damages one's sense of

Prolonged exposure to sulfur fumes permanently damages one's sense of smell. In one important study, 100 workers from sulfur-emitting factories and a control group of 100 workers from other occupations were asked to identify a variety of chemically reproduced scents, including those of foods, spices, and flowers. On average, the factory workers successfully identified 10 percent of the scents compared to 50 percent for the control group.

Each of the following, if true, weakens the argument EXCEPT:

(A)
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