Which one of these is a plant virus ?

Options

A. (a) TMV
B. (b) HIV
C. (c) Retrovirus
D. (d) SV 40

Answer

To determine which one of the provided options is a plant virus, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The question presents several options, among which we need to identify the plant virus.

2. **Analyze Option A - TMV**:
- TMV stands for Tobacco Mosaic Virus.
- This virus is known to infect tobacco plants and members of the Solanaceae family.
- It causes a characteristic mosaic pattern of discoloration on the leaves of infected plants.

3. **Analyze Option B - HIV**:
- HIV stands for Human Immunodeficiency Virus.
- This virus infects humans and is known for causing AIDS.
- It is a retrovirus that primarily affects the immune system.

4. **Analyze Option C - SV40**:
- SV40 stands for Simian Vacuolating Virus 40.
- This virus typically infects humans and monkeys, not plants.

5. **Conclusion**:
- From the analysis, it is clear that the only virus that infects plants is the Tobacco Mosaic Virus (TMV).
- Therefore, the correct answer is **Option A - TMV**.

### Final Answer:
**The plant virus among the options is A) Tobacco Mosaic Virus (TMV).**

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