Which of the following is an insulator?

Options

A. Carbon
B. Rubber
C. Silver
D. Copper

Answer

To determine which of the following materials is an insulator among Carbon, Rubber, Silver, and Copper, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Conductors and Insulators**:
- Conductors are materials that allow the flow of electric current due to the presence of free electrons.
- Insulators are materials that do not allow electric current to flow easily because they lack free electrons.

2. **Analyze Each Option**:
- **Carbon**: Carbon can conduct electricity in certain forms (like graphite) because it has free electrons. Therefore, it is not an insulator.
- **Rubber**: Rubber has a very high resistance and does not have free electrons available to conduct electricity. This makes rubber an insulator.
- **Silver**: Silver is one of the best conductors of electricity due to its abundance of free electrons. Thus, it is not an insulator.
- **Copper**: Copper is also a good conductor of electricity because it has free electrons. Hence, it is not an insulator.

3. **Conclusion**:
- Among the options provided, Rubber is the only material that acts as an insulator.

### Final Answer:
Rubber is the insulator among the given options.

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