Top soil is darker and

Options

A. Contains more Na and Mg
B. Is drier than subsoil
C. Contains more organic matter
D. Is wetter than subsoil

Answer

**Step-by-Step Solution:**

1. **Understanding Topsoil**: Topsoil is the uppermost layer of soil, typically ranging from 5 to 10 inches (approximately 13 to 25 centimeters) in depth. It is crucial for plant growth as it contains essential nutrients.

2. **Composition of Topsoil**: The topsoil is rich in organic matter, which includes decomposed plant and animal materials. This organic matter is often referred to as humus, which contributes to the darker color of the topsoil.

3. **Identifying Characteristics**: The darker color of topsoil is primarily due to the high concentration of organic matter. This organic matter is made up of decomposed leaves, dead plants, and other organic materials.

4. **Evaluating the Options**:
- **Option 1**: "It contains more sodium and magnesium" - This is not accurate as the darker color is not due to these minerals.
- **Option 2**: "It is drier than the subsoil" - This is incorrect; topsoil generally retains more moisture due to organic matter.
- **Option 3**: "It contains more organic matter" - This is correct as the topsoil is known for its richness in organic content.
- **Option 4**: "It is better than the subsoil" - This is subjective; while topsoil is more fertile, it doesn't mean it is better in all aspects.

5. **Conclusion**: Based on the analysis, the correct answer is **Option 3: It contains more organic matter**.

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