One of the following is not a natural process

Options

A. Transpiration
B. Guttation
C. Plasmolysis
D. Imbibition

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks us to identify which of the given options is not a natural process. This means we need to evaluate each option to determine if it occurs naturally in plants or if it is induced by artificial conditions.

2. **Analyzing the Options**:
- **Plasmolysis**: This is a process where plant cells lose water when placed in a hypertonic solution. It occurs when the osmotic pressure of the surrounding solution is greater than that inside the cell. This condition is not typically found in natural environments, making it an artificial process.
- **Transpiration**: This is the process of water loss from plant leaves through evaporation. It is a natural process essential for plant health and nutrient transport.
- **Guttation**: This is the secretion of water droplets from the tips of leaves. It occurs naturally when the soil moisture is high, and it is a normal physiological process in plants.
- **Inhibition**: This refers to the absorption of one substance by another, particularly in the context of water uptake by plant roots. This is also a natural process that occurs in plants.

3. **Identifying the Correct Answer**: Among the options analyzed, plasmolysis is the only process that occurs under artificial conditions (hypertonic solution) and is not a natural process that plants typically experience in their natural habitat.

4. **Conclusion**: Therefore, the answer to the question is that plasmolysis is not a natural process.

### Final Answer:
**Plasmolysis is not a natural process.**

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