**Core Concept:** Human Immunodeficiency Virus (HIV) is the virus responsible for AIDS (Acquired Immune Deficiency Syndrome), a disease that weakens the immune system, making the infected person more susceptible to opportunistic infections and cancers. HIV is classified into two main types: HIV-1 and HIV-2.

**Why the Correct Answer is Right:** HIV-2 is indeed found in West Africans, primarily in countries like Senegal, Guinea-Bissau, and parts of Ivory Coast, and is associated with a slower progression to AIDS compared to HIV-1.

**Why Each Wrong Option is Incorrect:**

A. HIV-1: This type of HIV is more prevalent globally, affecting millions of people worldwide. It is responsible for the vast majority of AIDS cases.

B. HIV-2: As mentioned above, HIV-2 is found in West Africans, but it does not specifically affect only West Africans. It is associated with a slower progression to AIDS.

C. HIV-3: There is no such type as HIV-3. HIV is classified into HIV-1 and HIV-2 only.

D. HIV found in Asians: HIV-1 is more prevalent in Asians, particularly in countries like India and Thailand, where it has led to a significant burden of AIDS cases.

**Clinical Pearl / High-Yield Fact:** The correct answer, HIV-2, is responsible for about 10% of AIDS cases globally, with a higher prevalence in West Africa. Understanding the differences between HIV-1 and HIV-2 is crucial for accurate diagnosis and treatment planning.