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Every possible means .However, nothing can him dying of cancer.
A. has tried; stop
B. have tried; keep
C. has been tried; prevent
D. have been tried; prevent
网友回答
A. has tried; stop
B. have tried; keep
(答案→)C. has been tried; prevent
D. have been tried; prevent
解析：可联系答.案.网客服索取。