📊 GMAT Exam Prep

A recent city initiative aimed at reducing plastic waste encouraged residents to use reusable shopping bags by providing them for free at local supermarkets. After six months, supermarket data showed a 10% decrease in the sale of disposable plastic bags. City officials concluded that the initiative was successful in significantly reducing plastic waste.

A Many residents who received free reusable bags already owned and regularly used reusable bags.
B The price of disposable plastic bags increased by 15% in city supermarkets during the six-month period.
C A neighboring city implemented a similar initiative that resulted in a 5% decrease in plastic bag sales.
D Environmental groups in the city reported an overall increase in the amount of plastic packaging on products sold.

✓ Correct Answer: Option B

If the price of disposable bags increased, residents might have reduced purchases due to cost, not the reusable bag initiative. This introduces an alternative cause for the observed decrease, weakening the officials' conclusion.

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