Adhesion is the result of -

Options

A. hydrogen bonding between the water molecules
B. Transpiration pull
C. High surface tension
D. Attraction of water molecules to polar surface / hydrophilic wall of the xylem tube.

Answer

**Step-by-Step Solution:**

1. **Understanding Adhesion**: Adhesion refers to the attraction between water molecules and other substances. In the context of plants, this typically involves the attraction of water molecules to the polar surfaces of the xylem vessels.

2. **Identifying the Mechanism**: The primary mechanism responsible for adhesion is hydrogen bonding. Water molecules, being polar, can form hydrogen bonds with other polar surfaces, such as the hydrophilic walls of xylem tubes.

3. **Differentiating from Cohesion**: It is important to differentiate adhesion from cohesion. Cohesion is the attraction between water molecules themselves, while adhesion is the attraction between water molecules and different substances.

4. **Analyzing the Options**: The options provided in the question include:
- Cohesion (related to hydrogen bonding between water molecules)
- Transpiration pull (not directly related to adhesion)
- High surface tension (a property of water but not directly related to adhesion)
- Attraction of water molecules to polar surfaces (this is the definition of adhesion)

5. **Selecting the Correct Answer**: Based on the understanding that adhesion is the attraction of water molecules to polar surfaces, the correct answer is the fourth option: "Attraction of water molecules to polar surface and hydrophilic wall of xylem tube."

**Final Answer**: Adhesion is the result of the attraction of water molecules to polar surfaces and the hydrophilic walls of xylem tubes.

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