Identify the ions responsible for the absorption of light by chlorophyll.

Options

A. Magnesium
B. Calcium
C. Chloride
D. Hydroxide

Explanation

**Step-by-Step Solution:**

1. **Understanding Chlorophyll Composition**: Chlorophyll is a pigment found in plants that is crucial for photosynthesis. Its chemical formula includes various elements such as carbon (C), hydrogen (H), nitrogen (N), oxygen (O), and magnesium (Mg).

2. **Identifying Key Ions**: Among these elements, magnesium (Mg) is a significant ion that plays a vital role in the structure of chlorophyll. It is essential for the absorption of light.

3. **Role of Magnesium in Light Absorption**: Magnesium ions are central to the chlorophyll molecule, and they help in capturing light energy. Without magnesium, chlorophyll cannot function effectively, which means photosynthesis would be impaired.

4. **Conclusion**: Therefore, the primary ion responsible for the absorption of light by chlorophyll is magnesium.

**Final Answer**: The ion responsible for the absorption of light by chlorophyll is Magnesium (Mg).

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