Sunken stoma occur in

Options

A. Xerophytes
B. Hydrophytes
C. Mesophytes
D. Opsanophytes

Answer

### Step-by-Step Solution:

1. **Understanding Stomata**: Stomata are small openings on the surface of leaves that allow for gas exchange (CO2 in, O2 out) and transpiration (water vapor loss).

2. **Identifying Plant Types**: The question presents four options:
- A) Xerophytes
- B) Hydrophytes
- C) Mesophytes
- D) Obstinophytes

3. **Defining Xerophytes**: Xerophytes are plants adapted to survive in extreme dry conditions. They have special adaptations to minimize water loss.

4. **Stomatal Adaptations in Xerophytes**: Xerophytes typically have fewer stomata, and those that are present are often located in sunken pits. This adaptation helps to reduce water loss by creating a microenvironment that retains moisture around the stomata.

5. **Evaluating Other Options**:
- **Hydrophytes**: These are plants that thrive in aquatic environments and usually have a higher number of stomata to facilitate gas exchange in water.
- **Mesophytes**: These plants prefer moderate conditions and have a normal number of stomata.
- **Obstinophytes**: This term is not commonly used in botanical classifications.

6. **Conclusion**: Based on the adaptations of xerophytes and the presence of sunken stomata, the correct answer is A) Xerophytes.

### Final Answer:
Sunken stomata occur in **xerophytes**.

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