6.----- in the mountains for a week,the two students were fi

6._____ in the mountains for a week,the two students were finally saved by the local police.
A.Having lost B.Lost
C.Being lost D.Losing
为什么不选c 这个是不是属于省略句的原因 因为 省了 after the two students were lost 所以因为状语从句中主句主语 和从句主语一样所以省了 还是 ,是一种非谓语的用法.说这个是形容词然后直接可以这样用,我听不懂这样的解释.希望一言惊醒梦中人.