问题补充：
I think Jack does his homework than anyone else in his class.
A. careful
B. more carefully
C. the most carefully
D. more careful
答案：
A. careful
(答案→)B. more carefully
C. the most carefully
D. more careful
解析：句意：我认为在班里面杰克的作业比其它任何人做得都好。结合语境可知本句中表示和其它人的对比，故用副词的比较级，选B。
