Imagine That You Have Gone to Visit Your PSYC 1001

Imagine that you have gone to visit your PSYC 1001 professor during his office hours and find out that he has a time machine in his office. He explains that the time machine works, except for a programming glitch that restricts the destination of the machine. This particular time machine can only travel to the laboratories of past psychology researchers. Seeing as you are an avid first-year psychology student, you boldly ask your professor if you can take a ride to a past laboratory. Surprisingly, he agrees, so you hop in, ready to travel back in time
-You travel to the office of B.F.Skinner.You ask him how he thinks you can stop your bad habit of biting your nails.What does he suggest you do

A) Scare yourself with stories about terrible illnesses and infections caused by nail-biting.
B) Paint a vomit-inducing polish on your nails so you will learn to associate nail-biting with vomiting.
C) Reward yourself every time you make it a week without biting your nails.
D) Think about the reason why you bite your nails and work to correct that instead.