A person who is eating rice. His food contains

Options

A. Cellulose
B. Starch
C. Lactose
D. Protein

Answer

### Step-by-Step Solution:

1. **Identify the Food Item**: The question states that a person is eating rice. We need to analyze the nutritional content of rice.

2. **Nutritional Composition of Rice**: Rice is primarily a cereal grain. The average nutritional values for rice are approximately:
- Carbohydrates: 28.7 g
- Proteins: 2.36 g
- Fats: 0.19 g

3. **Determine the Main Nutrient**: From the nutritional values, it is evident that carbohydrates are the most abundant component in rice, making up the majority of its content.

4. **Evaluate the Options**:
- **Cellulose**: This is incorrect. Cellulose is found mainly in fruits and vegetables, not in rice.
- **Starch**: This is correct. Starch is a type of carbohydrate, and since carbohydrates are the main component of rice, this option is valid.
- **Lactose**: This is incorrect. Lactose is a sugar found in milk, not in rice.
- **Proteins**: While rice does contain proteins, the amount (2.36 g) is significantly lower than the carbohydrate content, making this option less relevant in the context of the question.

5. **Conclusion**: Based on the analysis, the main component in the food of a person eating rice is starch.

### Final Answer:
A person who is eating rice, his food mainly contains **starch**.

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