**Core Concept:** Obsessive-compulsive disorder (OCD) is a psychiatric disorder characterized by recurrent, intrusive thoughts (obsessions) and repetitive behaviors or mental acts (compulsions) that the affected person feels driven to perform due to a perceived danger or distress. It can manifest as excessive hand washing or other compulsive behaviors.

**Why the Correct Answer is Right:** In this question, the individual is excessively washing hands due to a fear of getting HIV (Human Immunodeficiency Virus), which is a correct answer and fits the definition of OCD. This excessive hand washing represents both obsessions (related to the fear of HIV) and compulsions (repeated hand washing).

**Why Each Wrong Option is Incorrect:**

A. This option is incorrect because the fear of HIV (Human Immunodeficiency Virus) is not a correct answer as it does not fit the definition of OCD.
B. This option is incorrect as it does not represent the core feature of OCD, which is the presence of obsessions and compulsions.
C. This option is incorrect as it does not address the excessive hand washing behavior or the underlying fear of HIV that drives the compulsion.
D. This option is incorrect as it does not address the presence of obsessions and compulsions in the context of OCD.

**Clinical Pearl / High-Yield Fact:** Obsessive-compulsive disorder is a common mental health condition that affects approximately 2% of the general population. It can co-occur with other mental health disorders, such as anxiety disorders, and is often treated with a combination of psychotherapy (e.g., cognitive-behavioral therapy) and medications like selective serotonin reuptake inhibitors (SSRIs).

**Correct Answer:** .