When Tommy Caught His Son Gil Smoking a Cigarette, He

When Tommy caught his son Gil smoking a cigarette, he sat in a seat in the garage and told him "you may not get up until you've smoked this entire pack of cigarettes." After the 20th cigarette, Gil was so sick that he promised he'd never smoke again. Tommy is using ________ to teach his son not to smoke.

A) aversion conditioning
B) positive reinforcement
C) in vivo graduated exposure
D) virtual reality therapy