In the gardens, the earthworms can be traced by -

Options

A. Analysis of the salinity of soil
B. Analysis of the alkalinity of soil
C. By their fecal deposition (worm casts)
D. Analysis of the fertility of soil

Answer

To trace earthworms in gardens, we can follow these steps:

1. **Understanding Earthworm Habitat**: Earthworms are primarily found in soil, where they play a crucial role in aerating and enriching it. They belong to the phylum Annelida.

2. **Identifying Earthworm Indicators**: One of the most significant indicators of earthworm presence in gardens is their fecal matter, known as worm castings. These castings are rich in nutrients and serve as a natural fertilizer.

3. **Recognizing Worm Castings**: Worm castings are small, dark pellets that can be found on the soil surface or mixed within the soil. They are often referred to as "worm poo" and are an excellent sign of healthy earthworm activity.

4. **Assessing Soil Fertility**: The presence of worm castings indicates not only the presence of earthworms but also contributes to the overall fertility of the soil. The more worm castings present, the healthier the soil is likely to be.

5. **Conclusion**: Therefore, the best way to trace earthworms in gardens is through their fecal deposition, which is the presence of worm castings.

**Final Answer**: C. Through their fecal deposition (worm castings).

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