Answer:
D) systematic desensitization.
Step-by-step explanation:
Systematic desensitization: In psychology, the term systematic desensitization is described as the behavioral technique that is used to treat anxiety, phobia, and intense fear. By using this technique, the psychologist engages a person or client in various ways of relaxation exercise and therapy and moderately exposes the person or client into anxiety-provoking stimulus, for example, place, object, animal, etc. Systematic desensitization is based on the classical conditioning principle.
In the question above, the approach used by Sal's therapist is systematic desensitization.