Only then how much damage had been caused.
A. had she realized
B. she realized
C. did she realize
D. she had realized
网友回答
A. had she realized
B. she realized
(答案→)C. did she realize
D. she had realized
解析：这题考查倒装句的用法：only+副词 then，后面用部分倒装，即将助动词did放在主语前，句意是：只有那时他才知道造成多大的损失。选C。