AIDS is caused by

Options

A. Rubeola virus
B. Varicella virus
C. Human immunodeficiency virus
D. Treponema pallidum

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the causative agent of AIDS.

2. **Understand the Options**: The options provided are:
- a) Rubeola virus
- b) Varicella virus
- c) Human Immunodeficiency Virus (HIV)
- d) Treponema pallidum

3. **Evaluate Each Option**:
- **Option a: Rubeola virus**: This virus causes measles, not AIDS. Therefore, this option is incorrect.
- **Option b: Varicella virus**: This virus is responsible for chickenpox, not AIDS. Hence, this option is also incorrect.
- **Option c: Human Immunodeficiency Virus (HIV)**: This is the virus that causes AIDS (Acquired Immunodeficiency Syndrome). This option is correct.
- **Option d: Treponema pallidum**: This bacterium causes syphilis, which is a sexually transmitted disease, not AIDS. Thus, this option is incorrect.

4. **Conclusion**: The correct answer to the question "AIDS is caused by" is **Human Immunodeficiency Virus (HIV)**.

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