Final answer:
A client who compulsively looks at his or her reflection is most likely showing symptoms of body dysmorphic disorder, as it involves an obsessive focus on perceived physical imperfections and is often associated with eating disorders. The answer is option 3.
Step-by-step explanation:
A client who compulsively looks at his or her reflection in the mirror is most likely exhibiting symptoms of body dysmorphic disorder (BDD). BDD is a mental health disorder where a person obsessively focuses on perceived flaws in their appearance, often not noticeable to others.
This behavior is distinct from disorders such as panic disorder, which is characterized by sudden episodes of intense fear, hoarding disorder, where there is persistent difficulty discarding possessions, and obsessive-compulsive disorder (OCD), which involves repetitive behaviors or mental acts that an individual feels driven to perform in response to an obsession or according to rules that must be applied rigidly.
Considering the specific behavior of obsessively looking in the mirror, BDD is a fitting diagnosis, especially given that the majority of people with body dysmorphic disorder also have an eating disorder, further linking the behavior to concerns about body image.