Which one of the following pairs, is not correctly matched?

Options

A. IAA - Cell wall elongation
B. Abscisic acid - Stomata closure
C. Gibberellic acid - Leaf fall
D. Cytokinin - Cell division

Answer

To determine which pair is not correctly matched, we need to analyze each option provided in the question. Let's break it down step by step.

### Step 1: Analyze IAA (Indole Acetic Acid)
- **Function**: IAA is a plant hormone that promotes cell wall elongation.
- **Conclusion**: This pair is correctly matched.

### Step 2: Analyze Abscisic Acid
- **Function**: Abscisic acid is known for its role in stomatal closure, especially during drought conditions.
- **Conclusion**: This pair is correctly matched.

### Step 3: Analyze Gibberellic Acid
- **Function**: Gibberellic acid is a plant hormone that promotes growth and is involved in processes such as seed germination and stem elongation. It does not promote leaf fall.
- **Conclusion**: This pair is incorrectly matched as gibberellic acid does not cause leaf fall.

### Step 4: Analyze Cytokinin
- **Function**: Cytokinins are hormones that promote cell division and growth in plants.
- **Conclusion**: This pair is correctly matched.

### Final Conclusion
Based on the analysis, the pair that is not correctly matched is:
- **Gibberellic Acid - Leaf Fall** (This is the incorrect pair).

### Answer
The incorrect pair is: **Gibberellic Acid - Leaf Fall**.

---