Although police could be seen everywhere, they seemed to be searching the houses almost ________.
A.at ease
B.at random
C.at risk
D.at length
网友回答
B解析介词短语辨析。at ease安心;自在;不拘束; at random胡乱；at risk处于危险中；at length终于，最后,详细地；句意：尽管随处可以看见警察，但是他们似乎是在胡乱的搜查各个房子。