A lymphokine involved in defensive reaction against viruses is

Options

A. Interleukin
B. Endorphin
C. Interferon
D. Both B and C.

Answer

To answer the question, "A lymphokine involved in defensive reaction against viruses is," we will analyze the options provided and identify the correct lymphokine.

### Step-by-Step Solution:

1. **Understanding Lymphokines**:
- Lymphokines are a subset of cytokines that are produced by lymphocytes. They play a crucial role in the immune response, particularly in communication between cells and in the defense against pathogens.

2. **Analyzing the Options**:
- The options given are:
- A) Interleukin
- B) Endorphins
- C) Interferon
- D) Both B and C

3. **Evaluating Interleukins**:
- Interleukins (IL) are indeed cytokines that facilitate communication between immune cells. However, they are not specifically known for their role in directly defending against viral infections. Thus, interleukins are not the correct answer.

4. **Evaluating Endorphins**:
- Endorphins are neuropeptides that primarily function in the brain to reduce pain and induce feelings of pleasure. They are not involved in the immune response against viruses. Therefore, endorphins are also not the correct answer.

5. **Evaluating Interferons**:
- Interferons are a group of signaling proteins that are produced and released by host cells in response to the presence of viruses. They play a significant role in the immune response by inhibiting viral replication and activating immune cells. Therefore, interferons are indeed involved in the defensive reaction against viruses.

6. **Conclusion**:
- Based on the analysis, the correct answer to the question is **C) Interferon**.