in the mountains for a week, the two students were finally saved by the local police．
A.Having lostB.LostC.Being lostD.Losing在线课程B
解析：
此题考查的是分词作状语．题意为：在山区失踪了一周以后，这两个学生最终被当地的警察解救了．分词与主语之间的关系是被动关系，故排除A、D．分词所表示的动作先于谓语动词之前完成，排除C项．故答案为B．如①He was lost in thought．他想得很入神．②Lost in thought, he didn't hear the noise．他想得很入神，没有听到外面的吵闹声．