Assertion : Increasing carbon dioxide causes global warming
Reason : Carbon dioxide does not allow solar radiations re-radiated by earth to escape into space.

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.

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Increasing carbon dioxide causes global warming." This implies that as the levels of carbon dioxide in the atmosphere rise, the Earth's temperature also increases.

2. **Understanding the Reason**: The reason provided is that "Carbon dioxide does not allow solar radiations re-radiated by earth to escape into space." This means that carbon dioxide traps heat in the atmosphere, preventing it from escaping back into space.

3. **Explaining Global Warming**: Global warming refers to the gradual increase in the Earth's average temperature due to the accumulation of greenhouse gases like carbon dioxide. These gases trap heat in the atmosphere, leading to a warming effect.

4. **Role of Carbon Dioxide**: Carbon dioxide is a greenhouse gas that is transparent to incoming short-wave solar radiation but absorbs and re-emits long-wave radiation (heat) that the Earth emits. This process keeps the heat within the atmosphere, contributing to the greenhouse effect.

5. **Conclusion**: Both the assertion and the reason are correct. The assertion about increasing carbon dioxide causing global warming is supported by the reason that carbon dioxide prevents heat from escaping into space. Therefore, the assertion and reason are linked, with the reason providing an explanation for the assertion.

### Final Answer:
Both the assertion and the reason are correct, and the reason explains the assertion.

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