Silk mainly consists of :-

Options

A. Keratin
B. Fibroin
C. Collagen
D. Elastin

Answer

**Step-by-Step Solution:**

1. **Understanding Silk Composition**: Silk is primarily made up of proteins. The two main proteins found in silk are fibroin and sericin.

2. **Identifying the Main Protein**: Among these, fibroin is the most significant component, constituting about 70-80% of silk. Sericin, on the other hand, makes up the remaining 20-30%.

3. **Analyzing the Options**: The question provides four options: carotene, fibroin, collagen, and elastin. We need to determine which one is primarily associated with silk.

4. **Evaluating Each Option**:
- **Carotene**: This is not related to silk; it is a pigment found in plants and is responsible for the orange color in carrots.
- **Fibroin**: This is indeed a protein that is a major component of silk.
- **Collagen**: This is a protein found abundantly in animals, but it is not a component of silk.
- **Elastin**: This protein provides elasticity in various tissues but is not related to silk.

5. **Conclusion**: Based on the analysis, the correct answer to the question "Silk mainly consists of:" is fibroin.

**Final Answer**: Silk mainly consists of fibroin.

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