Pigment system-II is concerned with

Options

A. reduction of `CO_(2)`
B. flowering
C. photolysis of water
D. none

Answer

**Step-by-Step Solution:**

1. **Understanding Pigment System II**: Pigment System II, also known as Photosystem II (PSII), is a crucial component of the photosynthetic process in plants. It plays a significant role in the light-dependent reactions of photosynthesis.

2. **Role of Photosystem II**: The primary function of Photosystem II is to absorb light energy, which is then used to energize electrons. This process initiates the conversion of light energy into chemical energy.

3. **Water Splitting (Photolysis)**: One of the key reactions associated with Photosystem II is the photolysis of water. This process involves the splitting of water molecules into oxygen, protons, and electrons. The reaction can be summarized as:
\[ 2H_2O \rightarrow 4H^+ + 4e^- + O_2 \]
This reaction occurs on the inner side of the thylakoid membrane.

4. **Conclusion**: Given the options provided in the question, we can conclude that Photosystem II is primarily concerned with the photolysis of water. Therefore, the correct answer is option 3.

5. **Final Answer**: Hence, the correct answer is option 3: Photolysis of water.

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