Antiviral proteins are known as :

Options

A. Antigens
B. Vaccines
C. Interferons
D. Rh-factor

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of antiviral proteins. We need to identify the specific term used to describe these proteins that help in fighting viral infections.

2. **Identifying Antiviral Proteins**: Antiviral proteins play a crucial role in the immune response against viral infections. They are produced by cells in response to viral infections.

3. **Recognizing the Correct Term**: The specific type of antiviral proteins we are looking for is known as "interferons." Interferons are a class of cytokines that are important in the immune response.

4. **Function of Interferons**: Interferons are released by virus-infected cells and serve to signal neighboring uninfected cells to enhance their defenses against potential viral infection. This helps in protecting the surrounding cells from being infected.

5. **Reviewing Other Options**:
- Option 1: Antigen - This refers to substances that induce an immune response, not antiviral proteins.
- Option 2: Vaccines - These are preparations used to induce immunity, not proteins.
- Option 4: Rh factor - This is related to blood type and is not relevant to antiviral proteins.

6. **Conclusion**: Based on the information and the elimination of other options, the correct answer is that antiviral proteins are known as "interferons."

**Final Answer**: Antiviral proteins are known as interferons.

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