answer: The doctor asks #Person1# to quit smoking because #Person1#'s x-ray result shows there's tar built up in #Person1#'s lung and it causes shortness of breath.
documents: #Person1#: Okay, doctor, tell it to me straight.
  #Person2#: If you want to live much longer you have to give up smoking.
  #Person1#: I've tried before. Everything I've tried doesn't work.
  #Person2#: Maybe with the choice of life or death before you, you will find it easier.
  #Person1#: May I see that x-ray again?
  #Person2#: See all these black areas? That's tar built up in your Lungs.
  #Person1#: And that is what's causing my shortness of breath.
  #Person2#: Look at it this way, when you quit, you will save money, time and your life!