Modern shoe soles are made of

Options

A. Plastic
B. Synthetic rubber
C. Vulcanised rubber
D. Mixture of plastic and rubber

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the materials used in modern shoe soles.

2. **Analyzing the Options**: The options given are:
- a) Plastic
- b) Synthetic rubber
- c) Vulcanized rubber
- d) Mixture of plastic and rubber

3. **Evaluating Option a) Plastic**:
- Plastic is known to be brittle and hard.
- Since shoe soles need to be flexible and comfortable, plastic is not suitable for this purpose.
- **Conclusion**: This option is incorrect.

4. **Evaluating Option b) Synthetic rubber**:
- Synthetic rubber is a man-made material that is flexible and durable.
- It is designed to withstand wear and tear, making it an ideal choice for shoe soles.
- **Conclusion**: This option is likely correct.

5. **Evaluating Option c) Vulcanized rubber**:
- Vulcanized rubber is also chemically derived but is not as flexible as synthetic rubber.
- While it has some durability, it may not provide the same level of comfort and flexibility as synthetic rubber.
- **Conclusion**: This option is less suitable compared to synthetic rubber.

6. **Evaluating Option d) Mixture of plastic and rubber**:
- A mixture of plastic and rubber may inherit the brittleness of plastic, making it less flexible.
- This combination may not provide the necessary comfort for shoe soles.
- **Conclusion**: This option is also incorrect.

7. **Final Conclusion**: After evaluating all options, the best material for modern shoe soles is **synthetic rubber** due to its flexibility and durability.

**Final Answer**: The modern shoe soles are made of **synthetic rubber**.

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