The good conductor of electricity is:

Options

A. graphite
B. diamond
C. phosphorus
D. carborundum

Explanation

To determine which of the given options is a good conductor of electricity, let's analyze each option step by step.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are graphite, diamond, phosphorus, and carbon random.

2. **Understand the Nature of Each Option**:
- **Graphite**: Graphite is an allotrope of carbon. It has a layered structure where each carbon atom is bonded to three others, leaving one free electron per atom. This free electron allows graphite to conduct electricity.
- **Diamond**: Diamond is another allotrope of carbon, but in this structure, each carbon atom is bonded to four other carbon atoms in a tetrahedral arrangement. This structure does not allow for free electrons, making diamond a poor conductor of electricity.
- **Phosphorus**: Phosphorus is a non-metal and does not have free electrons to conduct electricity effectively. It is generally considered a poor conductor.
- **Carbon Random**: This is a mixture of silicon and carbon, and while it may have some conductive properties, it is not known for being a good conductor of electricity.

3. **Evaluate Conductivity**: Among the options, graphite stands out due to its unique structure that allows for the movement of free electrons, enabling it to conduct electricity effectively.

4. **Conclusion**: Based on the analysis, the good conductor of electricity among the given options is **graphite**.

### Final Answer:
The good conductor of electricity is **graphite**.

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