Soil erosion can be prevented by

Options

A. raising forests
B. deforestation
C. excessive use of tertiliser
D. overgrasing by animals

Explanation

**Step-by-Step Solution:**

1. **Understanding Soil Erosion:**
- Soil erosion is the process where the top layer of soil is removed or displaced by various agents such as wind, water, grazing animals, and human activities.

2. **Preventive Measures:**
- To prevent soil erosion, several methods can be employed:
- **Intensive Cropping:** Growing crops intensively helps to bind the soil, preventing it from being washed or blown away.
- **Afforestation:** Planting more trees helps to hold the soil together and reduces erosion.
- **Sowing Grass:** Planting grass on barren land can help bind the soil and prevent erosion.
- **Planting Xerophytes:** These are plants adapted to dry environments that can also help stabilize the soil.
- **Terrace Farming:** This method involves creating flat areas on slopes to slow down water flow and allow soil to settle.
- **Contour Bunding:** Building small embankments along the contours of the land helps to prevent soil loss from wind and water.
- **Conservation Tillage:** This method reduces soil disturbance and helps maintain soil structure.
- **Windbreaks:** Planting rows of trees and shrubs can act as barriers against wind, reducing wind erosion.
- **Proper Drainage:** Creating drainage canals around fields helps manage excess rainwater and reduces soil erosion.

3. **Identifying Correct Options:**
- Among the options provided (raising forest, deforestation, excessive use of fertilizers, overgrazing by animals), raising forests (planting trees) is a method that prevents soil erosion. The other options contribute to soil erosion.

4. **Conclusion:**
- The correct answer to the question "Soil erosion can be prevented by" is **raising forests**.

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