Which of the following sentences is INCORRECT？A．A city has more traffic than a small town.

Which of the following sentences is INCORRECT？

A．A city has more traffic than a small town.

B．We could do the work better with a few less supervisors..

C．He can drive there in fewer than 20 minutes.

D．There are more accidents than before.

请帮忙给出正确答案和分析，谢谢！