Capillary pores are

Options

A. Percolation pores
B. Macropores
C. Micropores
D. Ultra-micropores.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about "capillary pores" and provides four options: percolation pore, macropore, micropore, and ultramicropore.

2. **Definition of Capillary Pores**: Capillary pores are small spaces in the soil that allow water to move through them via capillary action. This action occurs due to the adhesive and cohesive properties of water.

3. **Analyzing the Options**:
- **Percolation Pore**: These pores allow water to move deeper into the soil but are not specifically related to capillary action.
- **Macropore**: These are larger pores that facilitate the movement of air and water but are not involved in capillary action.
- **Micropore**: These are small pores that are crucial for capillary action, allowing water to be absorbed and retained in the soil.
- **Ultramicropore**: These are even smaller than micropores and do not play a significant role in water movement for plants.

4. **Identifying the Correct Answer**: Based on the definitions and functions of the pores, micropores are the ones that facilitate capillary action and are essential for water retention in the soil. Therefore, the correct answer is **micropore**.

5. **Conclusion**: The correct answer to the question "Capillary pores are" is **micropores**.

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