The removal of fertile top soil from land by wind or water is called soil :

Options

A. corrosion
B. erosion
C. effusion
D. diffusion

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes the removal of fertile topsoil from land by wind or water.

2. **Identifying the Process**: The process of removing the top layer of soil, which is rich in nutrients and essential for plant growth, is a significant environmental issue.

3. **Defining Soil Erosion**: The correct term for the removal of fertile topsoil by natural forces like wind and water is "soil erosion."

4. **Causes of Soil Erosion**: Soil erosion can occur due to various factors, including deforestation (removal of trees), heavy rainfall, and poor agricultural practices that leave the soil exposed.

5. **Consequences of Soil Erosion**: The removal of topsoil leads to decreased soil fertility, which negatively impacts plant growth and agricultural productivity.

6. **Conclusion**: Therefore, the answer to the question is that the removal of fertile topsoil from land by wind or water is called "soil erosion."

**Final Answer**: Soil erosion.

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