GMAT Critical Reasoning (CR) | Re: A certain mayor has proposed a fee of five dollars per day

Definitely B. E says that the vehicles cause 20% congestion on workdays. But it does not weaken mayor's argument as he may still want to reduce 20% congestion with his fee. However, B clearly shows that car users already pay more for private transport and 5 dollars more will not stop them from using it.

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