A thunderstorm is accompanied by

Options

A. cyclone
B. tornado
C. lightning
D. earthquake

Explanation

**Step-by-Step Solution:**

1. **Understanding Thunderstorms**: A thunderstorm is a weather phenomenon characterized by the presence of thunder and lightning. It typically occurs when warm, moist air rises and cools, leading to the formation of cumulonimbus clouds.

2. **Conditions for Thunderstorms**: Thunderstorms are usually associated with the collision of large clouds. This collision can create conditions conducive to electrical discharges.

3. **Electrical Discharge**: During a thunderstorm, there is a significant discharge of electricity due to the buildup of static charges in the clouds. This discharge is what we observe as lightning.

4. **Sound of Thunder**: Along with lightning, thunderstorms produce the sound of thunder. The sound is generated by the rapid expansion of air heated by the lightning strike.

5. **Conclusion**: Therefore, a thunderstorm is accompanied by lightning and the sound of thunder. The correct answer to the question is that thunderstorms are accompanied by lightning.

**Final Answer**: A thunderstorm is accompanied by lightning.

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