A cotton filled quilt keeps a person warm in winter because

Options

A. Cotton is a good insulator.
B. A cotton quilt is light.
C. A log of air is trapped in a cotton quilt.
D. Cotton can be easily fluffed up.

Explanation

To understand why a cotton-filled quilt keeps a person warm in winter, let's break down the explanation step by step.

### Step-by-Step Solution:

1. **Understanding Insulation**:
- Insulation is the property of a material that prevents heat from passing through it. Good insulators help retain heat, keeping the warmth inside.

2. **Properties of Cotton**:
- Cotton is known to be a good insulator. It does not conduct heat well, which means it can help keep the heat generated by our body from escaping into the colder environment.

3. **Role of Air**:
- When a cotton quilt is used, it traps air within its layers. Air is also a good insulator of heat. The trapped air between the layers of cotton prevents heat loss.

4. **Heat Retention**:
- As our body generates heat, this heat warms up the air that is trapped inside the quilt. Since the quilt is closed on all sides, the warm air cannot escape, which keeps the person warm.

5. **Conclusion**:
- Therefore, a cotton-filled quilt keeps a person warm in winter primarily because it traps a layer of air, which is a good insulator, preventing the heat from escaping and maintaining warmth.

### Final Answer:
A cotton-filled quilt keeps a person warm in winter because it traps a layer of air, which is a good insulator of heat, preventing heat loss from the body.

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