Assertion : Classical smog is oxidising smog whereas photochemical smog ie reducing smog.
Reason : Classical smog occurs in warm, dry and sunny climate whereas photochemical smog occurs in cool humid climate .

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the c orrect explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

To solve the question, we will analyze the assertion and the reason provided, and then determine their validity.

### Step 1: Analyze the Assertion
The assertion states that "Classical smog is oxidizing smog whereas photochemical smog is reducing smog."

- **Classical Smog**: This type of smog is primarily composed of sulfur dioxide (SO2) and particulate matter. It occurs in cold, humid conditions and does not require sunlight for its formation. Classical smog is generally considered to be reducing in nature because it contains reducing agents like SO2.

- **Photochemical Smog**: This type of smog occurs in the presence of sunlight and is formed from the reaction of sunlight with pollutants such as nitrogen oxides and volatile organic compounds. Photochemical smog is oxidizing in nature due to the presence of ozone and other oxidants formed during these reactions.

**Conclusion for Assertion**: The assertion is incorrect because classical smog is reducing, while photochemical smog is oxidizing.

### Step 2: Analyze the Reason
The reason states that "Classical smog occurs in warm, dry, and sunny climate whereas photochemical smog occurs in cool humid climate."

- **Classical Smog**: As mentioned earlier, classical smog occurs in cold, humid conditions, typically during the winter months. It does not occur in warm and sunny climates.

- **Photochemical Smog**: This type of smog occurs in warm, dry, and sunny conditions, as it requires sunlight for its formation.

**Conclusion for Reason**: The reason is also incorrect because it reverses the climatic conditions for both types of smog.

### Final Conclusion
Both the assertion and the reason are false. Therefore, the correct answer to the question is that both the assertion and the reason are incorrect.

### Answer:
Both assertion and reason are false.

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