Assertion : Overcropping reduces soil fertility.
Reason : Soil fertility depends upon the soil composition.

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 "Overcropping reduces soil fertility."
- This means that when crops are planted continuously in the same soil without giving it time to recover, the soil loses its nutrients.

2. **Understanding the Reason:**
- The reason provided is that "Soil fertility depends upon the soil composition."
- Soil composition refers to the various components that make up the soil, including minerals, organic matter, water, and air.

3. **Analyzing the Assertion:**
- Overcropping leads to the depletion of essential nutrients in the soil because the same crops are taking out the same nutrients repeatedly without replenishment.
- This results in reduced soil fertility over time.

4. **Analyzing the Reason:**
- While it is true that soil fertility is influenced by soil composition, it is not the only factor. Other factors such as water retention, drainage, and even the presence of microorganisms also play significant roles in determining soil fertility.

5. **Conclusion:**
- The assertion is correct: overcropping does reduce soil fertility.
- The reason is also correct but does not fully explain the assertion, as it overlooks other important factors affecting soil fertility.
- Therefore, the correct answer is that both the assertion and reason are true, but the reason does not justify the assertion.

**Final Answer:**
- The correct option is 2: Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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