问题补充：
A reward of $1,000 will be given to can provide any clues to the case which has been investigated by the police for nearly half a year．
A. whoever
B. whomever
C. anyone
D. who
答案：
(答案→)A. whoever
B. whomever
C. anyone
D. who
解析：考查名词性从句。whoever无论谁，引导宾语从句，在从句中作主语，根据句意选A。
