Which of the following is not an essential micronutrient ?

Options

A. Boron
B. Sodium
C. Manganese
D. Molybdenum

Answer

To determine which of the following is not an essential micronutrient, we will analyze each option provided:

1. **Understanding Micronutrients**: Micronutrients are essential elements that plants require in small quantities for their growth and development. They include elements like iron, manganese, copper, molybdenum, zinc, boron, chlorine, and nickel.

2. **Evaluating the Options**:
- **Option A: Boron**: Boron is recognized as an essential micronutrient for plants. It plays a crucial role in cell wall formation and reproductive development.
- **Option B: Sodium**: Sodium is not considered an essential micronutrient for plants. While it can be beneficial in small amounts for certain plants, it is not required for the majority of plant species.
- **Option C: Manganese**: Manganese is an essential micronutrient involved in photosynthesis and enzyme activation.
- **Option D: Molybdenum**: Molybdenum is also an essential micronutrient, important for nitrogen fixation and enzyme function.

3. **Conclusion**: Based on the analysis, the only element listed that is not an essential micronutrient is **sodium (Option B)**.

Thus, the answer to the question "Which of the following is not an essential micronutrient?" is **B: Sodium**.

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