Stomata sunken in the substomatal cavities are called Sunken stomata which occur in

Options

A. hydrophyte
B. mesophyte
C. xerophyte
D. halophyte

Explanation

**Step-by-Step Solution:**

1. **Understanding Stomata**: Stomata are small openings on the surface of leaves that allow for gas exchange (carbon dioxide and oxygen) and transpiration (water loss).

2. **Identifying Sunken Stomata**: Sunken stomata are those that are located in cavities below the leaf surface, which helps to reduce water loss by creating a microenvironment with higher humidity.

3. **Analyzing Plant Types**:
- **Hydrophytes**: These are plants that grow in aquatic environments. They typically have stomata on the surface of their leaves for gas exchange, especially for those parts that float on water. Therefore, sunken stomata are not characteristic of hydrophytes.
- **Mesophytes**: These plants thrive in environments that are neither too dry nor too wet. They do have stomata for gas exchange, but they do not typically have sunken stomata.
- **Xerophytes**: These are plants adapted to dry environments, such as deserts. To minimize water loss, xerophytes often have sunken stomata located in substomatal cavities, making this the correct answer.
- **Halophytes**: These plants grow in saline soils. While they do have stomata, they are not specifically characterized by sunken stomata.

4. **Conclusion**: Based on the analysis, the type of plant that has sunken stomata in substomatal cavities is **xerophytes**.

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

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