Select the incorrect pair from the following.

Options

A. Photolysis of `H_(2)O` - Mn, Cl
B. Cation-anion balance - K, CI
C. Redox element Fe, Cu
D. Phloem transport B, Cu

Answer

To solve the question, we need to analyze each pair provided and determine which one is incorrect.

### Step-by-Step Solution:

1. **Analyze the First Pair: Photolysis of Water - Manganese and Chlorine**
- Photolysis of water occurs during photosynthesis, where water is split into oxygen, protons, and electrons.
- Manganese ions (Mn²⁺) play a crucial role as a cofactor in the oxygen-evolving complex of photosystem II.
- Chlorine is not directly involved in the photolysis of water.
- **Conclusion**: This pair is partially correct, but the inclusion of chlorine is questionable.

2. **Analyze the Second Pair: Cation, Anion Balance - Potassium and Chlorine**
- Cations (like potassium, K⁺) and anions (like chloride, Cl⁻) are essential for maintaining osmotic balance in plant cells.
- Potassium is crucial for processes such as the opening and closing of stomata.
- Chlorine is also involved in various physiological processes, including photosynthesis.
- **Conclusion**: This pair is correct.

3. **Analyze the Third Pair: Redox Elements - Iron and Copper**
- Iron (Fe) and copper (Cu) are both transition metals that can undergo oxidation and reduction reactions.
- They are involved in various biological redox processes, including electron transport chains.
- **Conclusion**: This pair is correct.

4. **Analyze the Fourth Pair: Phloem Transport - Boron and Copper**
- Boron is essential for the proper functioning of the phloem, as it helps in the formation of complexes with sugars and is vital for the transport of nutrients.
- Copper, while important for various enzymatic reactions, is not specifically required for phloem transport.
- **Conclusion**: This pair is incorrect because copper is not primarily involved in phloem transport.

### Final Answer:
The incorrect pair is **Phloem Transport - Boron and Copper**.

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