answer: #Person1# heard the telephone ringing while #Person1# didn't.
documents: #Person1#: Was that the telephone ringing?
  #Person2#: I didn't hear anything.
  #Person1#: I thought I heard it ring 2 or 3 times.
  #Person2#: Sometimes when the windows are open, you can hear the neighbor's phone.
  #Person1#: Well, I'm expecting an important phone call and I don't want to miss it.