Final answer:
Nina's hypnotist is using hypnosis to alter her eating habits, suggesting she drink water to manage her urge to eat between meals. Hypnosis is effective due to its capacity for heightened suggestibility in patients.
Step-by-step explanation:
Nina's hypnotist is using hypnosis to help her manage her overeating habits. This process involves a state of extreme self-focus and is especially effective for individuals who are highly susceptible to suggestions. As part of the therapeutic procedures under hypnosis, clinicians often use a combination of relaxation and suggestion to influence a patient's behavior and perceptions. In this case, the suggestion given by the hypnotist is a behavioral intervention aimed at substituting Nina's urge to eat between meals with drinking a glass of water. Based on the context of the question, the hypnotist makes a suggestive intervention, which is meant to guide Nina's future behavior under the influence of hypnosis. This suggestion is part of a broader strategy used for various therapeutic purposes, such as weight loss, pain management, and overcoming addictions.