Lightning occurs due to:

Options

A. Rain
B. Wind
C. Electric discharge
D. None of these

Answer

### Step-by-Step Solution:

1. **Understanding Lightning**: Lightning is a natural phenomenon that occurs during thunderstorms. It is a discharge of electricity that occurs between clouds or between a cloud and the ground.

2. **Charge Accumulation**: In a thunderstorm, clouds develop different charges. The upper part of the cloud typically accumulates positive charges, while the lower part accumulates negative charges.

3. **Ground Charges**: The ground also has a positive charge that interacts with the negative charge at the bottom of the cloud. This difference in charge creates an electric field.

4. **Poor Conductivity of Air**: Air is a poor conductor of electricity, which means it does not allow electric charges to flow freely. However, when the electric field becomes strong enough, it can overcome the air's resistance.

5. **Electrical Discharge**: When the electric field strength exceeds the air's insulating properties, a rapid discharge of electricity occurs. This discharge is what we see as lightning.

6. **Sound Production**: The rapid expansion and contraction of air due to the heat generated by the lightning creates sound waves, which we hear as thunder.

7. **Conclusion**: Therefore, lightning occurs due to the accumulation of electric charges in the clouds and the subsequent discharge of electricity when the conditions are right.

### Final Answer:
Lightning occurs due to electric charges.

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