When the fire ________, the people in the building lost their head and ran in all directions．
A.broke inB.broke awayC.broke outD.broke down在线课程C
考查短语辨析。句意“当那场火灾发生时，大楼里的人们手足无措，朝四面八方跑开。”A“打断，闯入”；B“离开，从......退出”；C“爆发”；D“失败，分解，出毛病”。故选C。