Viroids have

Options

A. double stranded DNA enclosed by a protein coat
B. double stranded RNA enclosed by a protein coat
C. single stranded RNA not enclosed by a protein coat
D. single stranded DNA not enclosed by a protein coat

Answer

To solve the question "Viroids have," we need to analyze the options provided and understand what viroids are.

### Step-by-Step Solution:

1. **Understanding Viroids**:
- Viroids are known to be small infectious agents that are primarily composed of nucleic acids. They are distinct from viruses in that they do not have a protein coat.

2. **Analyzing the Options**:
- **Option A**: Double stranded DNA enclosed by a protein coat - This describes a typical virus, not a viroid.
- **Option B**: Double stranded RNA enclosed by a protein coat - Again, this is characteristic of certain viruses, not viroids.
- **Option C**: Single stranded RNA not enclosed by a protein coat - This aligns with the definition of viroids, which consist of circular single-stranded RNA without a protein coat.
- **Option D**: Single stranded DNA not enclosed by a protein coat - This does not describe viroids, as they are not composed of DNA.

3. **Conclusion**:
- Based on the analysis, the correct answer is **C. Single stranded RNA not enclosed by a protein coat**. This is consistent with the known characteristics of viroids.

### Final Answer:
Viroids have **C. Single stranded RNA not enclosed by a protein coat**.

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