Which of these is a natural fibre?

Options

A. Acrylic
B. Coir
C. Polyester
D. Rayon

Explanation

**Step-by-Step Solution:**

1. **Understanding Natural Fibres:** Natural fibres are those that are obtained from plants or animals without any chemical processing. They are biodegradable and environmentally friendly.

2. **Analyzing the Options:**
- **Acrylic:** This is a synthetic fibre made from polymer, which means it is artificial and not a natural fibre.
- **Coir:** This is derived from the outer husk of coconuts. It is a natural fibre as it is obtained directly from a plant without any chemical alteration.
- **Polyester:** This is another synthetic fibre made from petroleum-based products, hence it is not a natural fibre.
- **Rayon:** Although rayon is derived from cellulose found in plants, it undergoes significant chemical processing to be made, classifying it as a manmade fibre.

3. **Identifying the Natural Fibre:** Among the options provided, coir is the only one that is a natural fibre, as it is directly obtained from the coconut plant without extensive chemical processing.

4. **Conclusion:** Therefore, the answer to the question "Which of these is a natural fibre?" is **Coir**.

**Final Answer:** Option number 2: Coir.

---