GMAT Critical Reasoning (CR) | A proposed ordinance requires all cyclists wear a helmet

A proposed ordinance requires that all cyclists wear a helmet when riding a bike. However, one cycling enthusiast argued that since more than ninety percent of bike-related accidents do not cause more than a scrape, mandatory helmet use would only marginally decrease the number of serious injuries caused by cycling.

Which of the following, if true, would most seriously weaken the cycling enthusiast's argument?

A. Most cyclists do not currently own bike helmets.

B. The cost of buying a proper
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