The digestion of a particular food in the small intestine produces amino acids. This food must contain mainly :

Options

A. carbohydrates
B. fats
C. vitamins
D. proteins

Answer

To solve the question, "The digestion of a particular food in the small intestine produces amino acids. This food must contain mainly:", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Digestion Site**: The question mentions that digestion occurs in the small intestine. This is where the final stages of digestion take place and nutrients are absorbed.

2. **Understand What Amino Acids Are**: Amino acids are the building blocks of proteins. They are produced when proteins are digested.

3. **Analyze the Types of Nutrients**: The question provides four options: carbohydrates, fats, vitamins, and proteins. We need to determine which of these nutrients is primarily digested to produce amino acids.

4. **Consider Carbohydrates**: Carbohydrates are broken down into sugars (like glucose) during digestion. They do not produce amino acids. Therefore, carbohydrates are not the main component in this case.

5. **Consider Fats**: Fats are digested into fatty acids and glycerol. They also do not yield amino acids. Thus, fats are not the correct answer.

6. **Consider Vitamins**: Vitamins are essential nutrients but do not undergo digestion to produce amino acids. They are absorbed as they are. Therefore, vitamins cannot be the answer.

7. **Consider Proteins**: Proteins are made up of long chains of amino acids. When proteins are digested, they are broken down into their constituent amino acids. The enzymes responsible for protein digestion include pepsin, trypsin, and chymotrypsin.

8. **Conclusion**: Since the digestion of the food in question produces amino acids, the food must primarily contain proteins.

### Final Answer:
The food must contain mainly **proteins**.

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