Major loss of water in transpiration occurs through

Options

A. Cuticle
B. Bark
C. Hydathodes
D. Stomata

Answer

### Step-by-Step Solution:

1. **Understanding Transpiration**:
- Transpiration is the process through which plants lose water vapor, primarily from their aerial parts. It plays a crucial role in water regulation and cooling of the plant.

2. **Identifying the Main Site of Water Loss**:
- The question asks where the major loss of water occurs during transpiration. The options provided are cuticle, bark, hydrothorax, and stomata.

3. **Evaluating the Options**:
- **Cuticle**: This is a waxy layer on the surface of leaves that helps reduce water loss but is not the primary site for water loss.
- **Bark**: This is the outer protective layer of stems and does not significantly contribute to transpiration.
- **Hydrothorax**: This term is not relevant in the context of plant transpiration.
- **Stomata**: These are small pores located on the leaf surface that allow for gas exchange and are the primary sites for water vapor loss.

4. **Role of Stomata**:
- Stomata are surrounded by guard cells that regulate their opening and closing. This regulation is crucial for controlling the rate of transpiration, allowing plants to balance water loss with gas exchange.

5. **Conclusion**:
- Based on the evaluation, the major loss of water in transpiration occurs through stomata.

### Final Answer:
The major loss of water in transpiration occurs through **stomata**.