The process of increasing fertility of soil by Earthworms is

Options

A. Worm casting
B. Vermicomposting
C. Compost bedding
D. None of the above

Answer

### Step-by-Step Solution:

1. **Understanding the Role of Earthworms**: Earthworms play a crucial role in soil fertility. They burrow through the soil, aerating it and allowing water and nutrients to penetrate more easily.

2. **Definition of Vermicomposting**: The process of using earthworms to enhance soil fertility is known as vermicomposting. This involves the breakdown of organic matter, such as kitchen waste and plant debris, by earthworms.

3. **Mechanism of Vermicomposting**: When earthworms consume organic waste, they digest it and excrete it in a form that is rich in nutrients. This excreted material is known as worm castings or vermicast, which is highly beneficial for plant growth.

4. **Benefits of Vermicomposting**: The worm castings improve soil structure, increase microbial activity, and enhance nutrient availability, making the soil more fertile and productive for agricultural purposes.

5. **Conclusion**: Therefore, the process of increasing the fertility of soil by earthworms is referred to as vermicomposting.

### Final Answer:
The process of increasing the fertility of soil by earthworms is called **vermicomposting**.

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