While ( ) in the room, we are all very excited.

While ( ) in the room, we are all very excited.
A、waited
B、waiting
C、to wait
D、wait
【正确答案】：B
【题目解析】：while 引导的从句主语如与主句主语一致，可以省略主语和系动词，用分词形式。句子含义是在房间等待时，我们都很兴奋。