Which one of the following pairs of elemnets is involved in the photolysis of water during light reaction of photosynthesis ?

Options

A. Manganese and chlorine
B. Manganese and potassium
C. Magnesium and molybdenum
D. Magnesium and chlorine

Explanation

To solve the question regarding which pair of elements is involved in the photolysis of water during the light reaction of photosynthesis, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Photolysis of Water**:
- Photolysis of water is the process where water molecules are split into oxygen, protons, and electrons using light energy. This occurs during the light-dependent reactions of photosynthesis.

2. **Identifying the Role of Photosystems**:
- In the light reactions, Photosystem II (PS2) absorbs light energy and transfers electrons to Photosystem I (PS1). This transfer creates a need for replacement electrons in PS2.

3. **Role of the Oxygen Evolving Complex**:
- To replenish the lost electrons in PS2, water molecules are split in a reaction facilitated by the oxygen-evolving complex (OEC), an enzyme that catalyzes this reaction.

4. **Elements Required for Photolysis**:
- The OEC requires specific elements as activators for the photolysis of water. The key elements involved in this process are manganese (Mn) and chloride (Cl).

5. **Result of Photolysis**:
- The photolysis of water results in the release of oxygen (O2), protons (H+), and electrons (e-). The electrons produced are then used to replace those lost by PS2.

6. **Conclusion**:
- Based on the above information, the correct answer to the question is the pair of elements **Manganese and Chlorine**, as they are essential for the photolysis of water during the light reactions of photosynthesis.

### Final Answer:
The correct pair of elements involved in the photolysis of water during the light reaction of photosynthesis is **Manganese and Chlorine**.

---