Protein digesting enzyme is

Options

A. Pepsin
B. Chymotrypsinogen
C. Trophoprotein
D. Amylase

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the protein digesting enzyme from the provided options.

2. **Analyze the Options**:
- **Option A: Pepsin**: Pepsin is known to be a protease, which means it digests proteins. It breaks down proteins into smaller peptides and is secreted by the chief cells of the stomach as part of gastric juice. Therefore, this option is a candidate for the correct answer.

- **Option B: Chymotrypsinogen**: This is an inactive precursor of the active enzyme chymotrypsin, which is involved in protein digestion. However, since the question specifies an enzyme and chymotrypsinogen is inactive, this option is incorrect.

- **Option C: Trophoprotein**: This term refers to normal proteins that are necessary for body nourishment and development. They are not enzymes and do not digest proteins, making this option incorrect.

- **Option D: Amylase**: Amylase is an enzyme that digests starch, not proteins. Therefore, this option is also incorrect.

3. **Conclusion**: After analyzing all the options, the only correct answer for the protein digesting enzyme is **Option A: Pepsin**.

**Final Answer**: Pepsin

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