Formation of London smog takes place in

Options

A. winter during daytime
B. summer during day time
C. summer during among time.
D. winter during morning time

Answer

### Step-by-Step Solution:

1. **Understanding London Smog**: London smog, also known as "the Great Smog," refers to a severe air pollution event that occurred in London, particularly noted during the winter of 1952.

2. **Identifying the Time of Occurrence**: The Great Smog happened in December 1952, which indicates that it took place during the winter season.

3. **Conditions Contributing to Smog Formation**: The formation of London smog was exacerbated by specific weather conditions, including cold weather, anticyclonic conditions, and a lack of wind. These conditions allowed pollutants to accumulate in the air.

4. **Pollutants Involved**: The primary pollutants contributing to the smog were airborne pollutants from coal combustion, including sulfur dioxide (SO2) and particulate matter.

5. **Duration of the Smog**: The smog lasted from December 5 to December 9, 1952, and dispersed quickly after a change in weather conditions.

6. **Conclusion**: Based on the information gathered, the formation of London smog primarily took place during the winter season and specifically in the morning time.

### Final Answer:
The formation of London smog takes place in **winter during morning time**.

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