You are trying to quit smoking.  You realized during self-mo…

You are trying to quit smoking.  You realized during self-monitoring that you most often smoke when you are studying and when you go out drinking with friends.  You have decided to stop keeping them in your home and to stop carrying cigarettes in your bag or pocket when you go out at night.  This method in a cognitive behavioral (CBT) approach to changing health behaviors in which the person changes their exposure to triggers for undesirable behaviors is called: