Many people are as to what to do when there is a fire.A. at a lossB. at riskC. at easeD.

问题补充：

Many people are as to what to do when there is a fire.

A. at a loss

B. at risk

C. at ease

D. at a distance

答案：

(答案→)A. at a loss

B. at risk

C. at ease

D. at a distance

解析：此处at a loss不知所措； at risk 冒着生命危险； at ease轻松地；at a distance遥远地；久远地；句意：许多人当有火灾的时候不知所措。根据句意选A。