ds RNA is found in

Options

A. Retrovirus
B. Reovirus
C. Rhabdo virus
D. Parvo virus

Explanation

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks where double-stranded RNA (ds RNA) is found. We need to identify which of the given options contains ds RNA as its genetic material.

2. **Evaluate the First Option - Retrovirus**: Retroviruses are known to have single-stranded RNA (ss RNA) as their genetic material. Since we are looking for double-stranded RNA, this option can be eliminated.

3. **Evaluate the Second Option - Reovirus**: Reoviruses are characterized by having double-stranded RNA as their genetic material. This matches the requirement of the question, making this a potential answer.

4. **Evaluate the Third Option - Revovirus**: Revoviruses also contain single-stranded RNA as their genetic material. Since we are looking for double-stranded RNA, this option can be eliminated.

5. **Evaluate the Fourth Option - Parvovirus**: Parvoviruses are known to have single-stranded DNA (ss DNA) as their genetic material. This does not meet the requirement for double-stranded RNA, so this option can also be eliminated.

6. **Conclusion**: After evaluating all the options, the only virus that contains double-stranded RNA is the reovirus. Therefore, the answer to the question is reovirus.

**Final Answer**: Reovirus contains double-stranded RNA.

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