All their attempts to rescue the child from the burning building were , and he died soon.
A. in place
B. in return
C. in vain
D. in ruins
网友回答
A. in place
B. in return
(答案→)C. in vain
D. in ruins
解析：A. in place在适当的位置，B. in return做为回报，C. in vain徒劳，D. in ruins成为废墟，句意：所有的救援着火的房子里面孩子的努力都徒劳，他很快就死了。根据句意选C。