An antiviral substance produced in response to viral infection for restricting its multiplication is

Options

A. Antigen
B. Antivirion
C. Interferon
D. Virion

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for an antiviral substance that is produced in response to viral infection and helps to restrict the multiplication of the virus.

2. **Identifying the Options**: The options given are:
- Antigen
- Antivirion
- Interferon
- Virion

3. **Analyzing Each Option**:
- **Antigen**: This is a foreign substance that is recognized by the immune system and can trigger an immune response. However, it does not directly restrict viral multiplication.
- **Antivirion**: This term refers to substances that act against virion particles, which are complete virus particles. This does not fit the description of a substance produced in response to infection.
- **Interferon**: This is a group of proteins produced by the immune system in response to viral infections. Interferons help to inhibit viral replication and boost the immune response.
- **Virion**: This is the complete virus particle, including its genetic material and protein coat. It is not a substance produced by the body.

4. **Conclusion**: The correct answer is **Interferon**, as it is specifically produced by the immune system in response to viral infections and plays a crucial role in limiting viral replication.

5. **Final Answer**: Interferon

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