Assertion : Deforestation increases carbon dioxide concentration in the atmosphere.
Reason : Deforestation may lead to desertification.

Options

A. (a) Both, Assertion and Reason, are true and Reason is the correct explanation of Assertion
B. (b) Both, Assertion and Reason, are true but Reason is not the correct explanation of Assertion
C. (c) If Assertion is true but Reason is false
D. (d) If Assertion is false but Reason is true

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "Deforestation increases carbon dioxide concentration in the atmosphere."
- Deforestation involves the removal of trees and forests, which play a crucial role in absorbing carbon dioxide (CO2) during photosynthesis. With fewer trees, less CO2 is absorbed, leading to an increase in atmospheric CO2 levels.

2. **Understanding the Reason:**
- The reason states that "Deforestation may lead to desertification."
- Desertification is the process by which fertile land becomes desert, typically as a result of drought, deforestation, or inappropriate agriculture. Deforestation can contribute to this process by disrupting the ecosystem, leading to soil erosion and loss of nutrients, which can turn once fertile lands into deserts.

3. **Evaluating the Relationship:**
- Both the assertion and the reason are true statements. Deforestation does increase CO2 levels, and it can also lead to desertification.
- However, the reason does not directly explain the assertion. While both statements are true, the increase in CO2 concentration is primarily due to the reduction in trees that absorb CO2, rather than the process of desertification itself.

4. **Conclusion:**
- Since both the assertion and reason are true, but the reason does not explain the assertion, the correct answer is: "Both assertion and reason are true, but reason is not the correct explanation for assertion."

**Final Answer:**
- The correct option is B: Both assertion and reason are true, but reason is not the correct explanation for assertion.

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