Cotton fibre is made up of

Options

A. Cellulose
B. Glycogen
C. Chitin
D. Starch

Answer

### Step-by-Step Solution:

1. **Understanding Cotton Fiber**: Cotton fibers are natural fibers that are primarily derived from the cotton plant. They are known for their softness and breathability.

2. **Identifying the Composition**: The main component of cotton fibers is cellulose. Cellulose is a complex carbohydrate that forms the structural component of plant cell walls.

3. **Explaining Cellulose**: Cellulose is made up of long chains of glucose molecules linked together. This polymer provides strength and rigidity to the plant structure.

4. **Evaluating Other Options**:
- **Glycogen**: This is a storage form of glucose in animals and fungi, not found in cotton fibers.
- **Chitin**: This is a structural component found in the exoskeletons of arthropods and in fungal cell walls, not related to cotton.
- **Starch**: This is another storage carbohydrate found in plants, but it is not a component of cotton fibers.

5. **Conclusion**: Based on the composition and structure of cotton fibers, the correct answer is that cotton fibers are made up of cellulose.

### Final Answer:
Cotton fiber is made up of **cellulose**.

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