Percolation and water hodling capacity of soil is dependent upon:

Options

A. Soil composition
B. Grain size
C. Aggregation
D. All of these.

Answer

To determine the factors that influence the percolation and water holding capacity of soil, we can analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Percolation and Water Holding Capacity**:
- Percolation refers to the process by which water moves through soil and rock layers. Water holding capacity is the ability of soil to retain water for use by plants.
- Both processes are influenced by various physical and chemical properties of the soil.

2. **Analyzing the Options**:
- **Option A: Soil Composition**:
- Soil composition includes the types of minerals, organic matter, and chemical ions present in the soil. Different compositions can affect how much water the soil can hold and how it interacts with water.
- **Option B: Grain Size**:
- The size of soil particles affects porosity and permeability. Larger grains create larger spaces between them, which can lead to faster drainage (lower water holding capacity), while smaller grains can hold water better due to their increased surface area.
- **Option C: Aggregation**:
- Soil aggregation refers to the clumping of soil particles into larger groups. Well-aggregated soils can improve water retention and percolation by creating more stable structures that hold water.
- **Option D: All of These**:
- This option suggests that all the factors mentioned (soil composition, grain size, and aggregation) contribute to the percolation and water holding capacity of soil.

3. **Conclusion**:
- Since all the factors mentioned in options A, B, and C influence the percolation and water holding capacity of soil, the correct answer is **Option D: All of These**.

### Final Answer:
The percolation and water holding capacity of soil is dependent upon **Option D: All of These**.

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