Assertion: Photochemical smog is a combination of photons with smoke and fog.
Reason: Photochemical smog is formed in the stratosphere.

Options

A. If both 'A' and 'R' are correct and 'R' is correct reason for 'A'.
B. If both 'A' and 'R' are correct and 'R' is not correct reason for 'A'.
C. If 'A' is true and 'R' is false.
D. If both 'A' and 'R' are false.

Answer

To analyze the given assertion and reason, let's break down the statements step by step:

### Step 1: Understand the Assertion
**Assertion:** Photochemical smog is a combination of photons with smoke and fog.

- Photochemical smog is primarily formed when sunlight (photons) reacts with pollutants like nitrogen oxides and volatile organic compounds in the atmosphere. However, it is not a combination of photons with smoke and fog. Instead, it is a chemical reaction that produces secondary pollutants, such as ozone, which contribute to smog formation.

### Step 2: Understand the Reason
**Reason:** Photochemical smog is formed in the stratosphere.

- Photochemical smog actually forms in the troposphere, which is the lowest layer of Earth's atmosphere, not in the stratosphere. The troposphere is where most weather events occur and where the majority of air pollution is concentrated.

### Step 3: Evaluate the Truth of Both Statements
- Both the assertion and the reason are incorrect:
- The assertion misrepresents the nature of photochemical smog.
- The reason incorrectly identifies the atmospheric layer where photochemical smog forms.

### Conclusion
Since both the assertion and the reason are false, the correct answer to the question is that both statements are incorrect.

### Final Answer
Both the assertion and the reason are false.

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