The most mutable virus is

Options

A. HIV
B. Chicken Pox virus
C. Influenza virus
D. Dengue virus

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the most mutable virus. The term "mutable" refers to the ability of an organism to change or adapt.

2. **Definition of Virus**: A virus is a biological agent that is infectious and can only reproduce inside the living cells of a host. It hijacks the host's cellular machinery to replicate itself.

3. **Meaning of Mutable**: The term "mutable" means prone to change. In the context of viruses, it refers to the virus's ability to undergo mutations and variations.

4. **Identifying the Most Mutable Virus**: Among various viruses, the Human Immunodeficiency Virus (HIV) is known for its high mutation rate. Each generation of HIV can exhibit changes in its genetic material, leading to variations from the parent virus.

5. **Mechanism of Mutation in HIV**: HIV mutates rapidly due to its ability to respond to selective pressures, such as the human immune system. This allows HIV to evade immune responses, making it highly adaptable.

6. **Conclusion**: Based on the information gathered, the most mutable virus is HIV (Human Immunodeficiency Virus), which is responsible for causing AIDS.

**Final Answer**: The most mutable virus is HIV (Human Immunodeficiency Virus).

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