Final answer:
Aversion therapy is the type of treatment that this method is an example of. It involves pairing a behavior with an unpleasant stimulus, and in this case, the client is taking disulfiram for alcohol use disorder and experiencing nausea and vomiting if alcohol is consumed.
Step-by-step explanation:
The method described in the question is an example of aversion therapy. Aversion therapy is a type of behavioral therapy that involves pairing a behavior with an unpleasant stimulus. In this case, the client is taking disulfiram, which causes unpleasant effects like nausea and vomiting if alcohol is consumed. By experiencing these unpleasant effects, the client is conditioned to associate alcohol with negative consequences, which can help them reduce or stop their alcohol use.