Smallest virus is

Options

A. Foot and Mouth virus
B. Alfalfa Mosaic virus
C. Pseudomonoas Pf
D. TMV.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the smallest virus.

2. **Research the Viruses**: To determine the smallest virus, we need to look at various known viruses and their sizes.

3. **Identify the Smallest Virus**: The smallest virus is the Foot and Mouth Disease Virus (FMDV).

4. **Size of the Virus**: The size of the Foot and Mouth Disease Virus ranges from approximately 0.008 to 0.012 microns (or 8 to 12 nanometers).

5. **Communicability**: The Foot and Mouth Disease Virus is highly communicable, meaning it can spread easily from one host to another.

6. **Comparison with Other Viruses**: While there are other small viruses, such as the Tobacco Mosaic Virus (TMV), they are larger than the Foot and Mouth Disease Virus.

7. **Conclusion**: Therefore, the smallest virus is the Foot and Mouth Disease Virus (FMDV).

**Final Answer**: The smallest virus is the Foot and Mouth Disease Virus (FMDV).

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