The presence of earthworm in the garden soil can be traced out by  

Options

A. moisture in soil
B. burrows
C. worm castings
D. all the above

Answer

To determine the presence of earthworms in garden soil, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Earthworm Habitats**: Earthworms thrive in moist environments, and they play a crucial role in soil aeration and nutrient cycling. Their presence can be inferred from certain indicators in the soil.

2. **Identifying Indicators**: The question provides several options: moisture in soil, burrows, and worm castings. We need to evaluate each option to determine which one is a reliable indicator of earthworm presence.

3. **Evaluating Moisture in Soil**: While earthworms do prefer moist soil, the presence of moisture alone does not confirm that earthworms are present. Many other factors can contribute to soil moisture.

4. **Evaluating Burrows**: Earthworms create burrows in the soil, but the presence of burrows does not definitively indicate that earthworms are present. Other organisms can also create similar structures.

5. **Evaluating Worm Castings**: Earthworms produce fecal matter known as worm castings. The presence of these castings is a direct indicator of earthworm activity in the soil. They enrich the soil with nutrients and improve its structure.

6. **Conclusion**: Among the options provided, the most reliable indicator of earthworm presence in garden soil is the presence of worm castings.

### Final Answer:
The presence of earthworm in garden soil can be traced out by **worm castings**.

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