The last micronutrient to be discovered was:

Options

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

Answer

To answer the question, "The last micronutrient to be discovered was:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand Micronutrients**: Micronutrients are essential elements required by plants in small quantities. They are also referred to as trace elements.

2. **List Common Micronutrients**: Some common examples of micronutrients include:
- Iron (Fe)
- Manganese (Mn)
- Copper (Cu)
- Molybdenum (Mo)
- Zinc (Zn)
- Boron (B)
- Chlorine (Cl)
- Nickel (Ni)

3. **Identify the Last Discovered Micronutrient**: Among the micronutrients listed, it is important to know which one was discovered last.

4. **Conclude with the Correct Answer**: The last micronutrient to be discovered is Nickel (Ni).

### Final Answer:
The last micronutrient to be discovered was Nickel.

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