Classical smog was first observed in

Options

A. Tokyo
B. New york
C. Sydney
D. London

Answer

**Step-by-Step Solution:**

1. **Understanding Classical Smog**: Classical smog is a type of air pollution that consists of a mixture of fog and smoke. It typically occurs in urban areas where there is a high concentration of pollutants.

2. **Components of Classical Smog**: The primary components that contribute to classical smog are sulfur dioxide (SO2) and particulate matter. These pollutants are often released into the atmosphere as a result of fuel combustion, particularly from industrial activities and vehicles.

3. **Historical Context**: To determine where classical smog was first observed, we need to look at historical records of air pollution incidents.

4. **Identifying the Location**: Among the given options (Tokyo, New York, Sydney, London), classical smog was first notably documented in London. This was particularly evident during the 19th and into the 20th century when industrialization was at its peak.

5. **Conclusion**: Based on the historical evidence and the characteristics of classical smog, the correct answer to the question is that classical smog was first observed in **London**.

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