-------What is it made Carl determined to give up smoking?
--------Watching how his father died in pain from lung cancer.
A. which
B. how
C. who
D. that
网友回答
A. which
B. how
C. who
(答案→)D. that
解析：通过分析句子结构，可知题目上文是强调句的特殊疑问句，基本结构是“特殊疑问词 + is / was + it that…?”因为去掉it is和that，剩下的是一个完整的句子，所以是强调句型。