Select the incorrectly matched pair.

Options

A. Magnesium (Mg)-Formation of mitotic spindle
B. Iron (Fe)-Formation of chlorophyll
C. Chlorine (Cl)-Anion cation balance in the cell
D. Sulphur(S)-Component of vitamins

Explanation

To solve the question of selecting the incorrectly matched pair, we will analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Identify the Pairs:**
- We have several pairs to evaluate. Each pair consists of a mineral and its associated function or role in plant biology.

2. **Evaluate Each Pair:**
- **Pair 1: Magnesium - Formation of Mitotic Spindle**
- Magnesium is essential for various metabolic processes, including photosynthesis, but it is not specifically known for its role in the formation of the mitotic spindle. Therefore, this pair is incorrectly matched.

- **Pair 2: Iron - Formation of Chlorophyll**
- Iron is indeed crucial for the formation of chlorophyll. It plays a significant role in photosynthesis. This pair is correctly matched.

- **Pair 3: Chlorine - Anion-Cation Balance in the Cell**
- Chlorine is involved in maintaining the anion-cation balance within plant cells. This pair is also correctly matched.

- **Pair 4: Sulfur - Component of Vitamins**
- Sulfur is a component of some vitamins and is essential for various biological functions. This pair is correctly matched as well.

3. **Conclusion:**
- After evaluating all the pairs, we find that the first pair (Magnesium - Formation of Mitotic Spindle) is the only incorrectly matched pair.

### Final Answer:
The incorrectly matched pair is **Magnesium - Formation of Mitotic Spindle**.

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