Reduction of water potential due to presence of solute is

Options

A. (a) turgor potential
B. (b) matric potential
C. (c) pressure potential
D. (d) osmotic potential

Answer

### Step-by-Step Solution:

1. **Understanding Water Potential**: Water potential is a measure of the potential energy of water in a system and is crucial for understanding how water moves in and out of cells. It is influenced by two main components: pressure potential and osmotic potential.

2. **Components of Water Potential**:
- **Pressure Potential (turgor potential)**: This is the pressure exerted by the fluid in the vacuole against the cell wall. It contributes to the rigidity of plant cells.
- **Osmotic Potential (solute potential)**: This is the potential of water to move across a semipermeable membrane due to solute concentration. It is directly proportional to the concentration of solutes in the solution.

3. **Effect of Solutes on Water Potential**: When solutes are added to a solution, they lower the water potential because they reduce the concentration of free water molecules. This phenomenon is described by the osmotic potential, which increases as solute concentration increases.

4. **Types of Solutions**:
- **Hypertonic Solution**: Higher solute concentration outside the cell, leading to water moving out of the cell, causing it to shrink. Here, osmotic potential is high, and water potential is low.
- **Isotonic Solution**: Equal solute concentration inside and outside the cell, resulting in no net movement of water.
- **Hypotonic Solution**: Lower solute concentration outside the cell, causing water to move into the cell, making it turgid. Here, osmotic potential is low, and water potential is high.

5. **Conclusion**: The reduction of water potential due to the presence of solute is specifically attributed to the osmotic potential. Therefore, the correct answer to the question is **osmotic potential**.

### Final Answer:
The reduction of water potential due to the presence of solute is called **osmotic potential**.

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