Which psychological disorder is marked by the repeated occurrence of obsessions and/or compulsions?

Obsessive-Compulsive Disorder (OCD) is characterized by the presence of persistent and unwanted thoughts known as obsessions, as well as repetitive behaviors or mental acts known as compulsions that an individual feels driven to perform. These obsessions can cause significant anxiety or distress, prompting individuals to engage in compulsive behaviors in an attempt to alleviate these feelings. This cycle of obsessions and compulsions is the hallmark of OCD, distinguishing it from other anxiety-related disorders, which may involve different symptoms and experiences.

For instance, post-traumatic stress disorder involves re-experiencing a traumatic event, while generalized anxiety disorder is characterized by excessive worry about various aspects of life without the specific obsessions and compulsions seen in OCD. Social anxiety disorder primarily focuses on the fear of social situations rather than the compulsive behaviors associated with OCD. Thus, OCD specifically encompasses the repetitive nature of obsessions and compulsions, making it the correct choice in this context.