Silkworms secrete fibre made of

Options

A. fat
B. cellulose
C. protein
D. nylon

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what type of fiber is secreted by silkworms.

2. **Identifying the Composition**: Silkworms secrete a fiber that is primarily made of protein.

3. **Process of Fiber Formation**: When the fiber secreted by silkworms is exposed to air, it hardens. This hardening process is essential for the formation of silk.

4. **Terminology**: The covering that the silkworm creates is called a "cocoon." This cocoon is what is processed to obtain silk fibers.

5. **Conclusion**: Therefore, the correct answer to the question is that silkworms secrete fiber made of protein.

6. **Eliminating Incorrect Options**:
- Option 1: Fat - This is incorrect as fat is an ester of fatty acids and not related to silk.
- Option 2: Cellulose - This is also incorrect as cellulose is a component of plant cell walls.
- Option 3: Nylon - This is a synthetic polymer and not related to the natural fiber secreted by silkworms.

7. **Final Answer**: The correct answer is that silkworms secrete fiber made of protein.

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