Assertion (A) : Presently, the global atmosphere is warming up.
Reason (R): The depletion of stratospheric ozone layer has resulted in increase in ultraviolet radiations reaching the Earth.

Options

A. If both Assertion `&` Reason are True `&` the Reason is a correct explanation of the Assertion.
B. If both Assertion `&` Reason are True but Reason is not a correct explanation of the Assertion
C. If Assertion is True but the Reason if False.
D. If both Assertion `&` Reason are false.

Answer

To analyze the assertion and reason provided in the question, we can follow these steps:

### Step 1: Understand the Assertion
The assertion states that "Presently, the global atmosphere is warming up." This is a widely accepted fact in climate science. Global warming refers to the long-term increase in Earth's average surface temperature due to human activities, primarily the emission of greenhouse gases.

### Step 2: Understand the Reason
The reason states that "The depletion of stratospheric ozone layer has resulted in an increase in ultraviolet radiations reaching the Earth." This statement is also true. The ozone layer protects the Earth from harmful ultraviolet (UV) radiation. When the ozone layer is depleted, more UV radiation reaches the Earth's surface, which can lead to various health and environmental issues.

### Step 3: Analyze the Relationship Between Assertion and Reason
While both the assertion and reason are true, they are not directly related in terms of causation. The warming of the global atmosphere is primarily due to the increase in greenhouse gases (like carbon dioxide, methane, and CFCs) that trap heat in the atmosphere. The depletion of the ozone layer and the increase in UV radiation are separate issues and do not directly cause global warming.

### Step 4: Conclusion
Based on the analysis, we can conclude that:
- Both the assertion and reason are true.
- However, the reason does not provide a correct explanation for the assertion.

Thus, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Final Answer
The correct option is: Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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