To find the incorrectly matched pair in the question regarding mineral nutrition, we will analyze each option step by step.
### Step 1: Identify the Options
We are given several pairs related to mineral nutrition, and we need to identify which one is incorrectly matched.
### Step 2: Evaluate Option 1 - Critical Elements
- **Critical Elements**: These are macronutrients that are commonly deficient in the soil and are required in large quantities by plants.
- **Elements Listed**: Nitrogen, Phosphorus, Potassium.
- **Evaluation**: This match is correct as these three elements are indeed considered critical elements.
### Step 3: Evaluate Option 2 - Mobile Elements
- **Mobile Elements**: These nutrients can move from older leaves to younger leaves when the plant is under stress or nutrient-deficient conditions.
- **Elements Listed**: Nitrogen, Phosphorus, Potassium, Chlorine, Magnesium, Molybdenum.
- **Evaluation**: The incorrect part of this option is that Calcium, Iron, and Sulfur are mentioned as mobile elements, which is not accurate. Calcium is generally considered immobile in plants. Therefore, this option is incorrectly matched.
### Step 4: Evaluate Option 3 - Balancing Elements
- **Balancing Elements**: These elements help mitigate toxic effects due to the deficiency of other nutrients.
- **Elements Listed**: Calcium, Magnesium, Potassium.
- **Evaluation**: This match is correct as these elements can help balance the effects of deficiencies in other nutrients.
### Step 5: Evaluate Option 4 - Framework Elements
- **Framework Elements**: These are primary elements that make up the protoplasm of cells.
- **Elements Listed**: Carbon, Hydrogen, Oxygen, Phosphorus, Sulfur.
- **Evaluation**: This match is also correct as these elements are fundamental components of biological molecules and are essential for life.
### Conclusion
After evaluating all options, we conclude that the incorrectly matched pair is found in **Option 2** where it incorrectly lists Calcium, Iron, and Sulfur as mobile elements.
### Final Answer
**The incorrectly matched pair is Option 2: Mobile Elements.**
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