题目内容：
根据以下资料，回答题： Davison knelt down close to the bottom of the basement stairs．He was saved for the moment by the thick fog which covered the street．Could the policemen be sure that he hadn’t turned round and run back into the main street? But they weren’t taking chances．Davison slowly went down the street as they searched all the doorways．
There wasn’t a light on in the basement flat behind him．That alone was dangerous．The po1icemen were coming close but they wouldn’t expect to find him in an occupied flat．There was a notice on the door which said “No milk till Monday”．he tore it down．He tried the door and found it was double locked．The footsteps came nearer very slowly．They must be searching thoroughly．He knew there was one chance because people were often careless，so he took out a knife，slipped it under the catch of the window and pushed upward until the window slid up．He climbed through quickly and fell on to a bed．He closed the window and turned on the light at once．
He heard steps coming towards the front door．On no account must the place seem empty．He looked for an electric point，and quickly connected the radio and turned it on．Then he opened the door opposite and found himself in the bathroom．Somebody—it could only be a policeman—rang the doorbell．Luckily he found what he wanted in the bathroom cupboard straightaway—a razor，a stick of shaving soap and a towel．He tied the towel over his collar and managed to soap over his neat beard and the ugly scar on his chin fairly thickened before the bell rang again．
Davison moved slowly to the front door and opened it．Two policemen stood outside and one of them had a dirty piece of paper in one hand．“We’ve just found this note，”he said．“As it says‘No milk till Monday’，I thought the flat might be empty and the light left on by mistake．”He looked at Davison carefully．
When Davison was hiding by the stairs，the policemen were————. A．searching the flats
B．running in the street
C．searching for him in the street
D．looking in the doorway
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