Why rayon is not considered a synthetic fibre?

Explanation

**Step-by-Step Solution:**

1. **Definition of Synthetic Fibres**: Synthetic fibres are man-made fibres that are produced from chemical substances, typically derived from petroleum or other synthetic processes. They are not derived from natural sources.

2. **Understanding Rayon**: Rayon is a type of fibre that is made from regenerated cellulose. The cellulose used to make rayon is primarily sourced from natural materials such as cotton linters and wood chips.

3. **Natural vs. Synthetic Origin**: Although the production of rayon involves human intervention and processing, the raw materials (cellulose) are derived from natural sources. This is a key distinction because synthetic fibres are entirely made from synthetic chemicals.

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