Which of the following is an insulator

Options

A. Human body
B. Graphite
C. Pure water
D. Copper

Answer

To determine which of the following options is an insulator, we will analyze each option provided: the human body, graphite, pure water, and copper.

### Step-by-Step Solution:

1. **Understanding Conductivity**:
- Conductivity refers to the ability of a material to allow the flow of electric current. Materials can be classified as conductors, insulators, or semiconductors based on their conductivity.

2. **Analyzing the Options**:
- **Human Body**: The human body contains a significant amount of water and electrolytes, which allows it to conduct electricity. Therefore, it is not an insulator.
- **Graphite**: Graphite is a form of carbon that can conduct electricity due to the mobility of its delocalized electrons. Hence, it is not an insulator.
- **Pure Water**: Pure or distilled water does not contain impurities or ions, which are necessary for conducting electricity. As a result, it does not allow the flow of electric current effectively and is considered an insulator.
- **Copper**: Copper is a well-known conductor of electricity, widely used in electrical wiring due to its excellent conductivity. Thus, it is not an insulator.

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

### Final Answer:
**Pure Water** is the insulator among the given options.

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