Which one of the following is not an essential mineral element for plants while the remaining three are

Options

A. Iron
B. Manganese
C. Cadmium
D. Phosphorus

Answer

**Step-by-Step Solution:**

1. **Understanding Essential Mineral Elements**: Essential mineral elements are those that are necessary for plant growth and development. They play crucial roles in various physiological processes within the plant.

2. **Identifying the Options**: The options given are:
- a) Iron
- b) Manganese
- c) Cadmium
- d) Phosphorus

3. **Evaluating Each Option**:
- **Iron**: This is an essential mineral element that is important for chlorophyll synthesis and various enzymatic functions in plants.
- **Manganese**: This is also an essential mineral element that plays a role in photosynthesis and enzyme activation.
- **Cadmium**: This is not an essential mineral element for plants. In fact, it is considered a toxic heavy metal that can be harmful to plant growth.
- **Phosphorus**: This is an essential mineral element that is crucial for energy transfer, photosynthesis, and nucleic acid synthesis in plants.

4. **Conclusion**: Based on the evaluation, cadmium is identified as the element that is not essential for plant growth and development.

5. **Final Answer**: The correct option is **c) Cadmium**.

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