Water-soluble inorganic nutrients go down into soil horizon and get precipitated an unavailable salts by the process of

Options

A. Fragmentation
B. Leaching
C. Catabolism
D. All of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the process by which water-soluble inorganic nutrients move down into the soil horizon and become precipitated as unavailable salts.

2. **Identifying Key Terms**:
- **Water-soluble inorganic nutrients**: These are nutrients that can dissolve in water and are essential for plant growth.
- **Soil horizon**: This refers to the different layers of soil, where various chemical and physical processes occur.
- **Precipitated and unavailable salts**: This means that the nutrients are transformed into forms that plants cannot use.

3. **Analyzing the Options**:
- **Option 1: Fragmentation**: This refers to breaking down materials into smaller pieces, which is not related to the movement of nutrients in soil.
- **Option 2: Leaching**: This is the process where soluble substances are washed out from the soil by water movement, leading to the downward movement of nutrients.
- **Option 3: Catabolism**: This is the breakdown of complex molecules into simpler ones, which is not relevant to the question.

4. **Choosing the Correct Process**: The process that describes the movement of water-soluble inorganic nutrients down into the soil and their subsequent precipitation as unavailable salts is **leaching**.

5. **Conclusion**: Therefore, the correct answer to the question is **leaching**.

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