Our stomach produces...... acid which helps in the digestion.

Options

A. `H_(2)SO_(4)`
B. `HNO_(3)`
C. `H_(2)PO_(3)`
D. HCI

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about the type of acid produced in the stomach that aids in digestion. We need to identify the correct acid from the given options: H₂SO₄ (sulfuric acid), HNO₃ (nitric acid), H₂PO₃ (phosphorous acid), or HCl (hydrochloric acid).

2. **Identifying the Correct Acid**: Among the options provided, hydrochloric acid (HCl) is known to be produced in the stomach. It is secreted by the gastric glands in the stomach lining.

3. **Role of Hydrochloric Acid**: HCl plays a crucial role in digestion. It helps to:
- Create an acidic environment in the stomach, which is necessary for the action of digestive enzymes.
- Break down food particles, making them softer and easier to digest.
- Activate the enzyme pepsin, which is essential for protein digestion.

4. **Function of Pepsin**: Pepsin is an enzyme that works optimally in an acidic environment. It breaks down proteins into smaller peptides. The presence of HCl is vital for pepsin to function effectively.

5. **Conclusion**: Based on the above points, the acid produced in the stomach that aids in digestion is hydrochloric acid (HCl).

**Final Answer**: HCl (hydrochloric acid)

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