–Why isn’t your brother good at math?
-- Because he thinks math is than any other subject.
A. difficult
B. much difficult
C. more difficult
D. the most difficult
网友回答
A. difficult
B. much difficult
(答案→)C. more difficult
D. the most difficult
解析：根据句子需要，本题所需要的是difficult的比较级，而difficult的比较级为more difficult，故选C