Integrated Reasoning (IR) | Re: In 1980 a researcher examined different indicators of hair health in a

[textarea]Explanation

I have solved this question just now and I am sure there might be some problem with the OA given with the source (This question belongs to Exampal GMAT Prep).

The logical answer shouldbe:

StrengthenBoth: Hat wearers use wax, which decreases hair loss, but less wax is needed in blackhats.
WeakenBoth: In Bali, white hats are only worn in closed places with nosunlight.

Here is the detailedexplanation:

The black Balinese hats are made of polyester, known to increase
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