Serotonin hormone is secreted by

Options

A. `alpha`- cells
B. `beta`- cells
C. `delta`- cells
D. All the above

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the secretion of the hormone serotonin and which cells are responsible for its production.

2. **Identifying the Options**: The options provided are alpha cells, beta cells, and delta cells. These cells are located in the pancreas.

3. **Function of Alpha Cells**: Alpha cells are known to secrete glucagon, a hormone that increases blood glucose levels. This is not related to serotonin.

4. **Function of Beta Cells**: Beta cells secrete insulin, which helps lower blood glucose levels. Again, this is not related to serotonin.

5. **Function of Delta Cells**: Delta cells are responsible for secreting serotonin. This hormone plays a role in inhibiting the secretion of insulin and glucagon.

6. **Conclusion**: Based on the information about the functions of the different pancreatic cells, we conclude that serotonin is secreted by delta cells.

7. **Final Answer**: Therefore, the correct answer is that serotonin hormone is secreted by delta cells of the pancreas (Option C).

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