Which of the following are chiefly digested in the stomach ?

Options

A. Carbohydrates
B. Proteins
C. Fats
D. Lipids

Explanation

To determine which substances are chiefly digested in the stomach, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The question asks which substances are chiefly digested in the stomach. The options typically include carbohydrates, proteins, and fats.

2. **Understand Carbohydrate Digestion**:
- Carbohydrates are primarily digested in the small intestine.
- The enzymes responsible for carbohydrate digestion, such as amylase and maltase, are produced in the small intestine.

3. **Understand Protein Digestion**:
- Proteins are mainly digested in the stomach.
- The enzyme responsible for protein digestion in the stomach is pepsin, which is secreted by the gastric glands.

4. **Understand Fat Digestion**:
- Fats (lipids) are also primarily digested in the small intestine.
- The enzyme responsible for fat digestion is lipase, which is produced in the pancreas and acts in the small intestine.

5. **Conclusion**:
- Based on the information above, the only substance that is chiefly digested in the stomach is **Protein**. Therefore, the correct answer is Protein.

### Final Answer:
The substance chiefly digested in the stomach is **Protein**.

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