The bright flash of light seen in a dark sky accompanied with a thunderstorm is

Options

A. Lightning
B. Collision
C. Earthquake
D. Electrolysis

Answer

To solve the question, "The bright flash of light seen in a dark sky accompanied with a thunderstorm is," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Phenomenon**: The question describes a scenario where there is a bright flash of light in the sky during a thunderstorm.

2. **Recall Common Weather Events**: During thunderstorms, there are specific natural phenomena that occur. Two of the most notable are lightning and thunder.

3. **Differentiate Between Lightning and Thunder**:
- **Lightning** is the bright flash of light that occurs due to the discharge of electricity in the atmosphere.
- **Thunder** is the sound produced by the rapid expansion of air heated by lightning.

4. **Conclude the Answer**: Since the question specifically asks for the bright flash of light, the correct answer is **lightning**.

5. **Select the Correct Option**: Based on the options provided (collision, earthquake, electrolysis), the only relevant option is lightning.

### Final Answer:
The bright flash of light seen in a dark sky accompanied by a thunderstorm is **lightning**.

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