Final answer:
Sam may have body dysmorphic disorder, a condition where individuals obsess over imagined defects in their appearance, and this is the most likely issue given his intense workout routine and dissatisfaction with his body size.
Step-by-step explanation:
Based on the information provided, Sam may have body dysmorphic disorder. This mental health condition involves an obsessive focus on perceived flaws in appearance which in reality may not be noticeable or may be minor. Despite engaging in an intense workout routine for several hours each day, if Sam still feels his body is too small and not muscular enough, it suggests he has a distorted view of his body image.
The other options listed, such as binge-eating disorder, anorexia nervosa, and orthorexia, do not align with Sam's belief that his body is too small, as these disorders typically involve different types of eating habits and concerns. For example, anorexia nervosa is characterized by eating very little and often exercising excessively due to a fear of weight gain and a distorted body image, seeing oneself as overweight even when underweight. On the other hand, binge-eating disorder involves compulsive overeating without subsequent purging behaviors.
The correct answer is b) Body dysmorphic disorder