Assertion : Ozone layer in the upper region of atmosphere protects earth from UV radiations of sun.
Reason : Ozone is a powerful oxidising agent as compared to oxygen.

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 correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

To analyze the given question, we need to evaluate both the assertion and the reason provided.

### Step 1: Evaluate the Assertion
The assertion states that "the ozone layer in the upper region of the atmosphere protects the Earth from UV radiations of the sun."

- The ozone layer is indeed located in the stratosphere, approximately 10 to 30 miles (or about 16 to 50 kilometers) above the Earth's surface.
- It absorbs the majority of the sun's harmful ultraviolet (UV) radiation, particularly UV-B and UV-C rays, which can cause skin cancer and other health issues.
- Therefore, this assertion is **true**.

### Step 2: Evaluate the Reason
The reason states that "ozone is a powerful oxidizing agent as compared to oxygen."

- Ozone (O₃) is indeed a stronger oxidizing agent than diatomic oxygen (O₂).
- This is because ozone can release nascent oxygen (O) when it decomposes, which is highly reactive and can oxidize other substances effectively.
- Thus, this reason is also **true**.

### Step 3: Determine the Relationship Between Assertion and Reason
Now we need to determine if the reason correctly explains the assertion.

- The assertion is about the protective role of the ozone layer against UV radiation, while the reason discusses the oxidizing properties of ozone.
- Although both statements are true, the reason does not explain why the ozone layer protects the Earth from UV radiation.

### Conclusion
Since both the assertion and the reason are true, but the reason does not provide a correct explanation for the assertion, the correct answer is:

**Option B: Both assertion and reason are true, but reason is not the correct explanation of assertion.**

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