Tim has never had traffic accident,because he drives________of all my friends.
A.more carefully B.most carefully C.carefully D.least carefully
B
【详解】
句意:Tim从来没有出过交通事故,因为我所有朋友中,他开车最小心。
考查副词的最高级。more carefully更小心地,副词的比较级;most carefully 最小心地,副词的最高级;carefully小心地,副词原形;least carefully最不小心地,根据所给空后面的of all my friends可知,应该用副词最高级,排除A和C,由前面的句子Tim has never had traffic accident可知,应该是最小心地,排除D,故选B。