Which one of the following is not a micronutrient for plants ?

Options

A. Magensium
B. Molybdenum
C. Boron
D. Zinc

Explanation

To determine which one of the following is not a micronutrient for plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Micronutrients**: Micronutrients are essential nutrients that plants require in small amounts. They play crucial roles in various physiological functions.

2. **List of Micronutrients**: There are eight recognized micronutrients essential for plant growth. These include:
- Iron (Fe)
- Manganese (Mn)
- Copper (Cu)
- Molybdenum (Mo)
- Zinc (Zn)
- Boron (B)
- Chlorine (Cl)
- Nickel (Ni)

3. **Identify Macronutrients**: In contrast to micronutrients, macronutrients are required by plants in larger quantities. An example of a macronutrient is Magnesium (Mg).

4. **Evaluate the Options**: If the question provides a list of elements, compare each one against the lists of micronutrients and macronutrients.

5. **Conclusion**: Based on the definitions and lists, identify which element does not belong to the group of micronutrients. In this case, Magnesium is not a micronutrient; it is classified as a macronutrient.

### Final Answer:
Magnesium is not a micronutrient for plants.

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