A fertile agricultural soil is _______ in colour as compared to soil one metre down, because it has _______.
Select the correct option to fill up the blanks above.

Options

A. Darker, More moisture
B. Lighter, Rich inorganic matter
C. Darker, Rich organic matter
D. Lighter, Abundance of minerals

Explanation

To fill in the blanks in the statement "A fertile agricultural soil is _______ in colour as compared to soil one metre down, because it has _______," we need to analyze the characteristics of fertile agricultural soil and the factors that contribute to its color.

### Step-by-Step Solution:

1. **Understanding Soil Layers**:
- Soil is composed of different layers, known as strata. The top layer is where crops are grown and is referred to as the topsoil.

2. **Color of Fertile Agricultural Soil**:
- Fertile agricultural soil is typically darker in color compared to the soil found one meter down. This darker color is a key characteristic of fertile soil.

3. **Reason for the Dark Color**:
- The dark color of fertile soil is primarily due to the presence of organic matter. This organic matter is known as humus.

4. **What is Humus?**:
- Humus is formed from the decomposition of plant and animal materials. It is rich in nutrients and contributes to the fertility of the soil.

5. **Conclusion**:
- Therefore, we can conclude that the correct answers to fill in the blanks are:
- "A fertile agricultural soil is **darker** in colour as compared to soil one metre down, because it has **humus**."

### Final Answer:
A fertile agricultural soil is **darker** in colour as compared to soil one metre down, because it has **humus**.

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