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Hi All,

Can someone please explain why answer B is correct in this stregthen question? Isn't B implying that the narrow floorboard costs less than the wide floorboard?

Thank you!

You need more narrow floorboards to cover the same area than if you used a wider floorboard. If they are the same price, than narrow floorboards would cost you more. Thus, it strengthens by removing the possibility that narrow floorboards are significantly cheaper.