In the immune system, interferons are a part of

Options

A. Physiological barries
B. Cellular barriers
C. Physical barriers
D. Cytokine barriers

Explanation

**Step-by-Step Solution:**

1. **Understanding Interferons**: Interferons are proteins that are produced and released by cells in response to the presence of pathogens, particularly viruses. They play a crucial role in the immune response.

2. **Analyzing the Options**:
- **Physiological Barriers**: These include physical and chemical barriers like skin, stomach acid, and enzymes in tears. They serve as the first line of defense but do not specifically involve interferons.
- **Cellular Barriers**: This refers to cells involved in the immune response, such as epithelial cells and phagocytic cells. While they are important, they do not specifically include interferons.
- **Physical Barriers**: These are structures like skin and mucous membranes that prevent pathogen entry. Again, this does not relate to interferons.
- **Cytokine Barriers**: This option refers to a group of signaling proteins, including interferons, that are involved in cell communication and immune responses. Interferons are indeed classified as cytokines.

3. **Conclusion**: Based on the analysis, the correct answer is that interferons are a part of **cytokine barriers**.

**Final Answer**: Interferons are a part of **cytokine barriers**.

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