Soil erosion can be prevented by:-

Options

A. Overgrazing
B. Removal of vegetation
C. Afforestation
D. Deforestation.

Answer

**Step-by-Step Solution:**

1. **Understanding Soil Erosion**:
- Soil erosion is the process where the top layer of soil is removed due to wind or water. This can lead to loss of fertile land and negatively impact agriculture and ecosystems.

2. **Identifying Causes of Soil Erosion**:
- One of the main causes of soil erosion is the lack of vegetation. Plants play a crucial role in holding the soil together with their root systems.

3. **Evaluating the Options**:
- **Overgrazing**: This occurs when herbivores eat too much vegetation. This leads to the removal of plants, which in turn means fewer roots to hold the soil, thus contributing to soil erosion. Therefore, this option is incorrect.
- **Removal of Vegetation**: Similar to overgrazing, removing vegetation also means that there are no roots to anchor the soil. This option is also incorrect.
- **Afforestation**: This is the process of planting trees and vegetation in an area where there were none before. By increasing the number of plants, roots will help hold the soil together, preventing erosion. This option is correct.
- **Deforestation**: This is the cutting down of trees and removal of vegetation. Like the previous options, this will lead to soil erosion as it removes the plants that stabilize the soil. Therefore, this option is incorrect.

4. **Conclusion**:
- The best method to prevent soil erosion from the given options is **afforestation**.

**Final Answer**: Soil erosion can be prevented by **afforestation**.

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