The last micronutrient to be discovered was:

Options

A. Ni
B. Si
C. Mo
D. Cu

Answer

**Step-by-Step Solution:**

1. **Understanding Micronutrients**: Micronutrients are essential elements required by plants in small amounts. They play crucial roles in various physiological processes.

2. **Identifying Micronutrients**: There are eight known micronutrients essential for plant growth. These include Iron, Manganese, Copper, Molybdenum, Zinc, Boron, Chlorine, and Nickel.

3. **Determining the Last Discovered Micronutrient**: Among these micronutrients, Nickel is recognized as the last one to be discovered.

4. **Conclusion**: Therefore, the answer to the question "The last micronutrient to be discovered was:" is Nickel.

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