Which of the following is an micronutrient ?

Options

A. Mg
B. Zn
C. Ca
D. P

Answer

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

### Step-by-Step Solution:

1. **Define Micronutrients and Macronutrients**:
- Micronutrients are nutrients required by plants in very small quantities. They play essential roles in plant growth and development.
- Macronutrients, on the other hand, are required in larger quantities and are crucial for the structural and functional aspects of plants.

2. **List the Given Options**:
- The options provided are:
- A) Magnesium
- B) Zinc
- C) Calcium
- D) Phosphorus

3. **Identify Each Nutrient's Classification**:
- **Magnesium**: This is classified as a macronutrient because it is required in larger amounts for plant growth.
- **Zinc**: This is classified as a micronutrient since it is needed in small quantities.
- **Calcium**: This is also a macronutrient, as it is required in larger amounts.
- **Phosphorus**: This is another macronutrient, necessary for various plant functions and required in larger quantities.

4. **Conclusion**:
- Among the options listed, the only micronutrient is **Zinc (Option B)**.

### Final Answer:
**Zinc** is the micronutrient among the given options.

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