Answer:
A. a proven way to maximize his profit margin.
Step-by-step explanation:
A is the only answer that makes sense in this scenario. If there is a proven way to maximize profit margin, it would mostly have a profit, yet the price would be low enough for their to be a large customer base. As many people like to join the 'bandwagon', a large customer base with high rating would potentially draw more customers, regardless if they need it or not.
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