The metal ion present in chlorophyll is:

Options

A. Fe
B. Mo
C. Mg
D. CI

Explanation

**Step-by-Step Solution:**

1. **Understanding Chlorophyll**: Chlorophyll is the green pigment found in plants that plays a crucial role in photosynthesis, allowing plants to absorb sunlight and convert it into energy.

2. **Identifying the Metal Ions**: The question asks for the metal ion present in chlorophyll. We need to consider the common metal ions associated with biological molecules.

3. **Evaluating Options**: The options provided include:
- Ferrous (iron)
- Molybdenum
- Magnesium
- Chlorine

4. **Analyzing Each Option**:
- **Ferrous (Iron)**: While iron is important for hemoglobin in red blood cells, it is not the metal ion in chlorophyll.
- **Molybdenum**: This metal is involved in photosynthesis but is not a component of chlorophyll itself.
- **Magnesium**: This is the key metal ion found in the structure of chlorophyll. It is essential for the chlorophyll molecule and plays a critical role in the process of photosynthesis.
- **Chlorine**: While chlorine is involved in plant processes, it does not serve as the metal ion in chlorophyll.

5. **Conclusion**: The metal ion present in chlorophyll is **Magnesium**.

**Final Answer**: Magnesium

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