Pepsin is secreted by

Options

A. Paneth cells
B. Zymogen cells of stomach
C. Zymogen cells of duodenum
D. Pancreas

Answer

### Step-by-Step Solution:

1. **Understanding Pepsin**: Pepsin is an enzyme that plays a crucial role in the digestion of proteins. It breaks down protein molecules into smaller peptides, which can then be further digested.

2. **Source of Pepsin**: Pepsin is secreted in its inactive form, known as pepsinogen. This is important because it prevents the enzyme from digesting the tissues of the stomach itself.

3. **Location of Secretion**: The secretion of pepsinogen occurs in the stomach. Specifically, it is produced by specialized cells known as gastric chief cells, which are also referred to as zymogen cells.

4. **Activation of Pepsinogen**: Once pepsinogen is secreted into the acidic environment of the stomach (due to hydrochloric acid), it is activated into pepsin.

5. **Conclusion**: Therefore, the correct answer to the question "Pepsin is secreted by" is the zymogen cells of the stomach.

### Final Answer:
Pepsin is secreted by the zymogen cells of the stomach.

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