Zn, Mo, Fe, Cu are

Options

A. trace elements
B. non-essential
C. macronutrients
D. none of these

Answer

**Step-by-Step Solution:**

1. **Identify the Elements**: The elements mentioned in the question are Zinc (Zn), Molybdenum (Mo), Iron (Fe), and Copper (Cu).

2. **Classify the Elements**: We need to classify these elements based on their role in plant nutrition.

3. **Understand Trace Elements**: Trace elements, also known as micronutrients, are essential nutrients that plants require in small amounts. They include elements like Copper, Zinc, Molybdenum, and Iron.

4. **Differentiate from Other Nutrients**:
- **Non-essential elements**: These are elements that are not required for plant growth. Examples include hydrogen, oxygen, and carbon.
- **Macronutrients**: These are nutrients required in larger quantities by plants, such as nitrogen, phosphorus, potassium (primary macronutrients), and calcium, magnesium, and sulfur (secondary macronutrients).

5. **Conclusion**: Since Zinc, Molybdenum, Iron, and Copper are required in trace amounts for plant growth, they fall under the category of trace elements or micronutrients.

6. **Final Answer**: Therefore, the correct classification for Zn, Mo, Fe, and Cu is that they are **trace elements**.

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