--We haven't heard form Jane for a long time. ---what do you suppose to her?
A. was happening
B. to happen
C. has happened
D. having happened
网友回答
A. was happening
B. to happen
(答案→)C. has happened
D. having happened
解析：通过上下文的理解, 这里说明那事已经发生,并对现在造成影响.