问题补充：
．the fact that doctors have warned that smoking causes cancer, people still keep on smoking.
A. Due t o
B. Thanks to
C. In case of
D. In spite of
答案：
A. Due t o
B. Thanks to
C. In case of
(答案→)D. In spite of
解析：考查短语辨析。Due to 由于，Thanks to 多亏了，In case of 以免，In spite of 尽管，句意：尽管这个事实医生警告了吸烟导致癌症，人们仍然继续吸烟。所以选A。
