Assertion (A) : Ozone is destroyed by solar radiation in upper streatosphere.
Reason (R) : Thinning of the ozone layer allows excessive UV radiations to reach the surface of earth.

Options

A. Both A and R are correct and R is the correct explanation of A
B. Both A and R are correct and R is not the correct explanation of A
C. Both A and R are not correct
D. A is not correct but R is correct

Explanation

To solve the assertion-reason question, we will analyze both the assertion (A) and the reason (R) step by step.

### Step 1: Analyze the Assertion (A)
The assertion states: "Ozone is destroyed by solar radiation in the upper stratosphere."
- **Evaluation**: This statement is incorrect. Ozone depletion primarily occurs due to human-made chemicals, particularly chlorofluorocarbons (CFCs), rather than solar radiation. Solar radiation does play a role in the natural cycle of ozone formation and destruction, but it is not the primary cause of ozone layer depletion.

### Step 2: Analyze the Reason (R)
The reason states: "Thinning of the ozone layer allows excessive UV radiations to reach the surface of the Earth."
- **Evaluation**: This statement is correct. The thinning of the ozone layer, which is caused by pollutants like CFCs, does indeed allow more ultraviolet (UV) radiation to penetrate through the atmosphere and reach the Earth's surface. This increased UV radiation can lead to harmful effects on living organisms, including skin cancer and other health issues.

### Step 3: Conclusion
- Since the assertion is incorrect and the reason is correct, we can conclude that the correct answer to the assertion-reason question is that the assertion (A) is false, while the reason (R) is true.

### Final Answer
Therefore, the correct option is D: Assertion is false, but Reason is true.

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