Phytohormone connected with closing of stomata is

Options

A. ABA
B. Kinetin
C. GA
D. IBA.

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the phytohormone that is connected with the closing of stomata in plants.

2. **Identifying the Options**: The options provided are:
- A) ABA (Abscisic Acid)
- B) Kinetin
- C) GA (Gibberellic Acid)
- D) IBA (Indolebutyric Acid)

3. **Analyzing Each Option**:
- **Option A: ABA (Abscisic Acid)**: This hormone is known as a stress hormone. It is released when the plant is under stress, such as during high transpiration rates. ABA helps to close the stomata to reduce water loss, making it the correct answer.
- **Option B: Kinetin**: This is a type of cytokinin that primarily promotes cell division and shoot development. It is not involved in stomatal closure.
- **Option C: GA (Gibberellic Acid)**: This hormone is associated with promoting stem elongation and is not related to stomatal closure.
- **Option D: IBA (Indolebutyric Acid)**: This is another type of auxin that is involved in root development and apical dominance, not in the closing of stomata.

4. **Conclusion**: Based on the analysis, the phytohormone connected with the closing of stomata is **ABA (Abscisic Acid)**.

### Final Answer:
The phytohormone connected with closing of stomata is **ABA (Abscisic Acid)**.

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