Earthworms are commonly found in

Options

A. Deep water
B. Saline water
C. Upper layer of soil
D. Air

Answer

**Step-by-Step Solution:**

1. **Understanding Earthworms' Habitat**: Earthworms are known to be soil-dwelling creatures. This means that they primarily live in the soil rather than in water or air.

2. **Analyzing the Options**:
- **Deep Water**: While earthworms can survive underwater for a limited time, they do not live in deep water. They are not adapted to thrive in aquatic environments.
- **Saline Water**: Earthworms are not found in saline water. They require a specific type of environment that is not salty.
- **Upper Layer of Soil**: This option aligns with the known habitat of earthworms. They live in the upper layers of soil where they can burrow and feed on organic matter.
- **Air**: Earthworms cannot live in air. They require moisture and soil for their survival.

3. **Conclusion**: Based on the analysis of the options, the correct answer is that earthworms are commonly found in the upper layer of soil.

**Final Answer**: Earthworms are commonly found in the upper layer of soil.

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