Mineral involved in photolysis of water are
(a) `Mn" "`(b) `Ca`
(c) `Mg" "`(d) `Cl`.

Options

A. a, b
B. a, b, d
C. c, d
D. a, b, c

Answer

To determine which minerals are involved in the photolysis of water, we need to analyze the options provided: Manganese (Mn), Calcium (Ca), Magnesium (Mg), and Chlorine (Cl).

### Step-by-Step Solution:

1. **Understanding Photolysis of Water**:
- Photolysis of water refers to the process where water molecules are split into hydrogen ions, oxygen, and electrons in the presence of light. This process occurs in the chloroplasts of plants during photosynthesis.

2. **Identifying the Minerals**:
- We need to evaluate each mineral to see if it plays a role in the photolysis of water.

3. **Manganese (Mn)**:
- Manganese is known to be involved in the photolysis of water. It acts as a cofactor in the water-splitting complex of photosystem II.

4. **Calcium (Ca)**:
- Calcium is also involved in the photolysis of water. It plays a role in stabilizing the structure of the photosystem and is essential for the proper functioning of the photosynthetic machinery.

5. **Magnesium (Mg)**:
- Magnesium is not directly involved in the photolysis of water. Instead, it is crucial for the activation of various enzymes and is a central component of chlorophyll, but it does not participate in the splitting of water.

6. **Chlorine (Cl)**:
- Chlorine is involved in the photolysis of water as well. It helps in maintaining the ionic balance and is involved in the overall process of photosynthesis.

7. **Conclusion**:
- The minerals involved in the photolysis of water are Manganese (Mn), Calcium (Ca), and Chlorine (Cl). Therefore, the correct answer includes options (a) Mn, (b) Ca, and (d) Cl.

### Final Answer:
The minerals involved in the photolysis of water are (a) Manganese, (b) Calcium, and (d) Chlorine.

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