Transpiration is completely absent in

Options

A. Xerophytes
B. Mesophytes
C. Submerged hydrophytes
D. Succulents at night

Answer

**Step-by-Step Solution:**

1. **Understanding Transpiration**: Transpiration is the process by which water vapor is lost from the aerial parts of plants, primarily through small openings called stomata. This process is essential for water regulation and nutrient transport within the plant.

2. **Analyzing the Options**:
- **Option 1: Xerophytes**: These are plants adapted to arid environments. They have mechanisms to minimize water loss, but they still undergo transpiration, albeit at a reduced rate. Therefore, this option is incorrect.

- **Option 2: Mesophytes**: These plants require a moderate amount of water and do transpire. They are not adapted to extreme conditions, so this option is also incorrect.

- **Option 3: Submerged Hydrophytes**: These are plants that live completely submerged in water. Since they are fully submerged, the process of transpiration is not applicable as they do not lose water through stomata in the same way terrestrial plants do. This makes this option correct.

- **Option 4: Sciohophytes at night**: Sciohophytes are plants that grow in shaded areas. While they may have reduced transpiration at night, they still transpire to some extent. Thus, this option is incorrect.

3. **Conclusion**: The correct answer is **Option 3: Submerged Hydrophytes**, as they do not undergo transpiration due to their complete submersion in water.