Infectious proteins are presents in

Options

A. Satellite viruses
B. Gemini viruses
C. Prions
D. Viroids

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the presence of infectious proteins in specific entities, which include satellite viruses, Gemini viruses, prions, and viroids.

2. **Defining Infectious Proteins**: Infectious proteins refer to proteins that can cause disease by inducing abnormal folding of normal cellular proteins, leading to various neurodegenerative diseases.

3. **Analyzing Each Option**:
- **Satellite Virus**: These are sub-viral agents that require a helper virus for replication. They do not consist of infectious proteins.
- **Gemini Virus**: This is a type of plant virus that contains genetic material (circular single-stranded DNA) but does not consist of infectious proteins.
- **Prions**: These are infectious agents composed entirely of protein. They cause diseases by inducing misfolding of normal proteins in the brain, leading to neurodegenerative conditions.
- **Viroids**: These are small infectious pathogens that consist solely of RNA and lack a protein coat (capsid). They do not contain infectious proteins.

4. **Conclusion**: Among the options provided, infectious proteins are specifically present in **prions**.

### Final Answer: **Prions**

---