Mark the incorrect match .

Options

A. Insulin - Zinc
B. Haemoglobin - Iron
C. Vitamin `B_(12)` - Cobalt
D. Chlorophyll - Chromium

Explanation

To solve the question of marking the incorrect match, we will analyze each option provided in the question step by step.

### Step 1: Analyze the first option - Insulin and Zinc
- Insulin is a hormone that regulates glucose levels in the blood.
- It contains zinc ions (Zn²⁺) as a part of its structure.
- **Conclusion**: This match is correct.

### Step 2: Analyze the second option - Hemoglobin and Iron
- Hemoglobin is a protein in red blood cells that carries oxygen.
- It contains iron ions (Fe²⁺) in its heme group, which is essential for oxygen binding.
- **Conclusion**: This match is correct.

### Step 3: Analyze the third option - Vitamin B12 and Cobalt
- Vitamin B12, also known as cobalamin, contains cobalt (Co²⁺) as its central metal ion.
- This cobalt ion is crucial for the biological activity of Vitamin B12.
- **Conclusion**: This match is correct.

### Step 4: Analyze the fourth option - Chlorophyll and Chromium
- Chlorophyll is the green pigment found in plants that is essential for photosynthesis.
- The central metal ion in chlorophyll is magnesium (Mg²⁺), not chromium (Cr).
- **Conclusion**: This match is incorrect.

### Final Conclusion
The incorrect match is **Chlorophyll and Chromium**. The correct metal ion in chlorophyll is magnesium.

### Answer
The correct option indicating the incorrect match is the **fourth option**: Chlorophyll - Chromium.

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