Smog is combination of

Options

A. air and water vapour
B. water and smoke
C. smoke and fog
D. fire and water

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what smog is a combination of. We need to identify the correct components that make up smog from the given options.

2. **Analyzing the Options**: The options provided are:
- Air and water vapor
- Water and smoke
- Smoke and fog
- Fire and water

3. **Historical Context**: Smog is a term that originated during the industrial revolution in the early 1900s. During this time, many industries released a significant amount of smoke into the atmosphere.

4. **Definition of Smog**: Smog is specifically defined as a mixture of smoke and fog. The smoke from industrial activities combines with fog (which consists of tiny water droplets in the air) to create smog.

5. **Conclusion**: Based on the definition and historical context, the correct answer to the question is that smog is a combination of smoke and fog.

**Final Answer**: Smog is a combination of smoke and fog.

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