Viruses with double stranded (ds) RNA are

Options

A. reoviruses
B. deoxyriboviruses
C. retroviruses
D. prophage

Answer

To solve the question "Viruses with double stranded (ds) RNA are," we will analyze the options provided and identify the correct answer step by step.

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question asks for viruses that have double-stranded RNA (dsRNA) as their genetic material.

2. **Identifying Types of Genetic Material**:
- Genetic material in viruses can be either DNA (deoxyribonucleic acid) or RNA (ribonucleic acid).
- Each of these can be single-stranded or double-stranded.

3. **Reviewing the Options**:
- **Option A: Reoviruses** - These are known to be part of the family Reoviridae, which is characterized by having double-stranded RNA as their genetic material.
- **Option B: Deoxyriboviruses** - This term refers to viruses with DNA, specifically deoxyribonucleic acid, which is not relevant to the question about RNA viruses.
- **Option C: Retroviruses** - These are single-stranded RNA viruses, which do not fit the requirement for double-stranded RNA.
- **Option D: Prophase** - This term refers to a stage in the cell cycle or a bacteriophage’s genome integrated into a host genome, and it is not a type of virus.

4. **Analyzing the Correct Option**:
- From the analysis, we see that Reoviruses (Option A) are indeed double-stranded RNA viruses, making it the correct choice.

5. **Conclusion**:
- Therefore, the correct answer to the question is **Option A: Reoviruses**.

### Final Answer:
Viruses with double stranded (ds) RNA are **Reoviruses**.