I'm not sure whether this is the room she left her dictionary. A. whereB. thatC. whichD.

问题补充：

Im not sure whether this is the room she left her dictionary.

A. where

B. that

C. which

D. in that

答案：

(答案→)A. where

B. that

C. which

D. in that

解析：考查定语从句：先行词是the room，定语从句中缺少地点状语，用where或in which引导定语从句，句意：我不确定是否这就是她丢了字典的房间。选A。