The virus responsible for causing AIDS primarily infects?

Options

A. Monocytes
B. Mast cells
C. Macrophages
D. Mucosal cells

Answer

**Step-by-Step Solution:**

1. **Identify the Virus Responsible for AIDS:**
- The virus that causes AIDS is known as HIV (Human Immunodeficiency Virus). It is classified as a retrovirus.

2. **Understand the Nature of HIV:**
- HIV is a retrovirus, which means its genetic material is RNA. This is a key characteristic that distinguishes it from other types of viruses.

3. **Recognize the Year of Discovery:**
- HIV was first identified in the year 1983, marking a significant milestone in the understanding of AIDS.

4. **AIDS as a Sexually Transmitted Disease:**
- AIDS is classified as a sexually transmitted disease (STD), which means it can be transmitted through sexual contact.

5. **Mechanism of Infection:**
- When HIV enters the body, it primarily targets the immune system. This is crucial because the immune system is responsible for defending the body against infections.

6. **Target Cells of HIV:**
- HIV primarily infects white blood cells (WBCs), specifically targeting macrophages. Macrophages are large white blood cells that play a vital role in the immune response by engulfing and digesting foreign particles.

7. **Impact on the Immune System:**
- The infection of macrophages by HIV leads to a weakened immune system, making it difficult for the body to fight off infections and diseases.

8. **Conclusion:**
- Therefore, the virus responsible for causing AIDS primarily infects macrophages, which are a type of white blood cell.

**Final Answer:**
The virus responsible for causing AIDS primarily infects macrophages (option 3).

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