Which of the following is a micronutrient

Options

A. Ca
B. Mg
C. K
D. Ni

Answer

To determine which of the given options is a micronutrient, we need to understand the difference between macronutrients and micronutrients in plant nutrition.

### Step-by-Step Solution:

1. **Identify the Nutrient Categories**:
- Macronutrients are nutrients that plants require in larger quantities. These typically include nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur.
- Micronutrients are required in smaller amounts and include elements such as iron, manganese, zinc, copper, molybdenum, boron, and nickel.

2. **Analyze the Given Options**:
- **Calcium**: This is a macronutrient, essential for cell wall structure and stability.
- **Magnesium**: This is also a macronutrient, important for chlorophyll production and enzyme function.
- **Potassium**: Another macronutrient, crucial for various physiological processes in plants.
- **Nickel**: This is classified as a micronutrient, essential for certain enzymatic processes and the growth of specific crops.

3. **Conclusion**:
- Among the options provided, nickel is the only element that qualifies as a micronutrient.

### Final Answer:
The correct answer is **nickel**.

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