Cotton fibre is

Options

A. sclerenchyma cell
B. collenchyma cell
C. sclereid
D. epidermal outgrowth

Answer

**Step-by-Step Solution:**

1. **Understanding Cotton Fiber**: Cotton fiber is derived from the cotton plant, scientifically known as *Gossypium*. It is a soft and fluffy fiber that grows around the seeds of the plant, serving as a protective case.

2. **Identifying the Composition**: The primary component of cotton fiber is cellulose, which is a polysaccharide that forms the structural component of plant cell walls.

3. **Analyzing the Options**: The question provides four options:
- Sclerenchyma cells
- Collenchyma cells
- Sclerid
- Epidermal outgrowth

4. **Evaluating Each Option**:
- **Sclerenchyma Cells**: These are typically dead cells with thickened secondary walls containing lignin, providing structural support. Therefore, this option is incorrect.
- **Collenchyma Cells**: These cells provide flexible support to growing parts of the plant. They are alive at maturity but do not form cotton fibers. Thus, this option is also incorrect.
- **Sclerid**: These are a type of sclerenchyma cell but are reduced forms and do not represent cotton fiber. Hence, this option is incorrect.
- **Epidermal Outgrowth**: Cotton fibers are indeed classified as epidermal outgrowths of the seeds. This option is correct.

5. **Conclusion**: Based on the analysis, the correct answer is that cotton fiber is an epidermal outgrowth.

**Final Answer**: Cotton fiber is an epidermal outgrowth.

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