Fibres have the characteristic features like
Thread forming solids
II. High tensile strength and high modulus
III. Crystalline nature Select the correct option

Options

A. I and II
B. Only III
C. II and III
D. All of these

Answer

To solve the question regarding the characteristics of fibers, we will analyze each statement provided in the question:

1. **Thread forming solids**:
- Fibers are indeed thread-forming solids. They are long, thin structures that can be spun into threads or yarns. This characteristic is fundamental to the definition of fibers.

**Conclusion**: This statement is true.

2. **High tensile strength and high modulus**:
- Fibers are known for their high tensile strength, which means they can withstand a lot of force without breaking. Additionally, they have a high modulus, indicating that they are stiff and resistant to deformation. This property is crucial for their use in textiles and other applications where strength and durability are required.

**Conclusion**: This statement is also true.

3. **Crystalline nature**:
- Many fibers, such as nylon and polyester, exhibit a crystalline structure. This crystalline nature contributes to their strength and stability. The arrangement of polymer chains in a crystalline form allows for better packing and stronger intermolecular forces.

**Conclusion**: This statement is true as well.

Given that all three statements are true, we can conclude that the correct option is the one that states all characteristics are valid.

**Final Answer**: All statements are correct.

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