A leafy shoot is enclosed air tightly in a flask. The flask become moist on the inner surface due to

Options

A. Guttation
B. Evaporation
C. Transpiration
D. Cooling effect

Answer

### Step-by-Step Solution:

1. **Understanding the Situation**: A leafy shoot is enclosed in a flask, and after some time, the inner surface of the flask becomes moist. This indicates that there is some form of water movement or change occurring.

2. **Identifying Possible Processes**: The options provided are:
- Guttation
- Evaporation
- Transpiration
- Cooling effect

3. **Analyzing Guttation**: Guttation is the process where water droplets are exuded from the tips or margins of leaves through specialized structures called hydathodes. This does not apply here as we are observing moisture on the flask's inner surface, not on the leaves themselves.

4. **Analyzing Evaporation**: Evaporation is the process where liquid water changes into vapor. While this could contribute to moisture, it does not explain why the inner surface of the flask becomes moist specifically due to the leafy shoot.

5. **Analyzing Transpiration**: Transpiration is the process by which water vapor is lost from the plant through small openings called stomata. When the water vapor released from the leaves comes into contact with the cooler glass of the flask, it condenses into water droplets, leading to the moist inner surface of the flask.

6. **Analyzing Cooling Effect**: The cooling effect refers to the temperature drop that occurs when vapor condenses into liquid. While this is a consequence of transpiration, it does not directly explain the moisture formation.

7. **Conclusion**: The correct answer to the question is that the flask becomes moist on the inner surface due to **transpiration**.

### Final Answer:
The flask becomes moist on the inner surface due to **transpiration**.

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