Find the incorrectly matched pair

Options

A. Critical element - N,P,K
B. Mobile elements - Ca,Fe,S
C. Balancing elements - Ca,Mg,K
D. Framework elements - C,H,O

Answer

To solve the question of finding the incorrectly matched pair among the given options, we will analyze each option step by step.

### Step 1: Analyze the first option - Critical Elements
- **Definition**: Critical elements are macronutrients that are commonly deficient in soils.
- **Elements listed**: Nitrogen, Phosphorus, and Potassium (N, P, K).
- **Conclusion**: This option is correctly matched as N, P, and K are indeed critical elements essential for plant growth.

### Step 2: Analyze the second option - Mobile Elements
- **Definition**: Mobile elements are nutrients that can be transported throughout the plant from one part to another.
- **Elements listed**: Calcium, Iron, and Sulphur.
- **Analysis**:
- Calcium is considered an immobile element.
- Iron and Sulphur are mobile elements.
- **Conclusion**: This option is incorrectly matched because Calcium is not a mobile element.

### Step 3: Analyze the third option - Balancing Elements
- **Definition**: Balancing elements help mitigate the toxic effects of other elements.
- **Elements listed**: Calcium, Magnesium, and Potassium.
- **Conclusion**: This option is correctly matched as all three elements serve as balancing elements in plants.

### Step 4: Analyze the fourth option - Framework Elements
- **Definition**: Framework elements are essential for the structure of biomolecules in plants.
- **Elements listed**: Carbon, Hydrogen, and Oxygen.
- **Conclusion**: This option is correctly matched since these elements are fundamental to plant structure and function.

### Final Conclusion
After analyzing all the options, the incorrectly matched pair is the second option: **Mobile Elements (Calcium, Iron, and Sulphur)**, as Calcium is not a mobile element.

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