Which one of the following is ss RNA ?

Options

A. TMV
B. `T_(2)`- bacteriophage
C. Pox virus
D. `phi xx 174`

Answer

To determine which of the given options is a single-stranded RNA (ssRNA) virus, we can analyze each option based on their genetic material.

### Step-by-Step Solution:

1. **Identify the Options**: We have four options to consider:
- TMV (Tobacco Mosaic Virus)
- T2 Bacteriophage
- 5174 (a type of bacteriophage)
- Pox Virus

2. **Understand the Nature of Each Virus**:
- **TMV (Tobacco Mosaic Virus)**: This virus is known to have positive-sense single-stranded RNA as its genetic material. It primarily infects plants, especially tobacco.
- **T2 Bacteriophage**: This is a virus that infects bacteria (specifically E. coli) and contains double-stranded DNA as its genetic material.
- **5174 (Bacteriophage)**: Similar to T2, this bacteriophage also infects bacteria and has single-stranded DNA as its genetic material.
- **Pox Virus**: This virus, known for causing smallpox, contains double-stranded DNA.

3. **Determine the Correct Answer**: From the analysis above, the only virus that contains single-stranded RNA is TMV (Tobacco Mosaic Virus).

4. **Final Conclusion**: Therefore, the answer to the question "Which one of the following is ss RNA?" is **TMV (Tobacco Mosaic Virus)**.