Chicken pox is caused by

Options

A. Varicella virus
B. Adeno virus
C. Bacteriophage
D. SV40 Virus.

Answer

**Step-by-Step Solution:**

1. **Identify the Disease:** The question asks about the causative agent of chicken pox.

2. **Understand Chicken Pox:** Chicken pox is a highly contagious disease characterized by a skin rash that forms small itchy blisters. It is important to note that chicken pox is also known as varicella.

3. **Identify the Causative Agent:** Chicken pox is caused by the varicella-zoster virus (VZV). This virus is responsible for the initial infection that leads to the disease.

4. **Evaluate the Options:**
- **Option A: Varicella Virus** - This is the correct answer as it is synonymous with the varicella-zoster virus.
- **Option B: Adenovirus** - This is incorrect as adenoviruses primarily cause respiratory illnesses.
- **Option C: Bacteriophage** - This is also incorrect; bacteriophages infect bacteria, not humans.
- **Option D: SV40 Virus** - This is incorrect as SV40 is a simian virus associated with certain tumors in animals, not chicken pox.

5. **Conclusion:** The correct answer to the question "Chicken pox is caused by" is **Varicella Virus**.

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