Identify the micronutrients among the following.

Options

A. Nitrogen
B. Potassium
C. Calcium
D. Iron

Explanation

**Step-by-Step Solution:**

1. **Understanding Micronutrients:**
- Micronutrients are essential nutrients that our body requires in very small quantities. They play crucial roles in various bodily functions.

2. **Differentiating Between Macronutrients and Micronutrients:**
- Macronutrients are nutrients needed in larger quantities, such as carbohydrates, proteins, and fats. In contrast, micronutrients include vitamins and minerals, which are required in smaller amounts.

3. **Analyzing the Given Options:**
- The options provided are:
- A) Nitrogen
- B) Potassium
- C) Calcium
- D) Iron

4. **Identifying Micronutrients from the Options:**
- **Nitrogen**: This is primarily a macronutrient, essential for plant growth but not classified as a micronutrient.
- **Potassium**: This is also considered a macronutrient, important for plant and human health but required in larger amounts.
- **Calcium**: While it is essential for health, it is generally classified as a macronutrient due to the larger quantities needed.
- **Iron**: This is a micronutrient, as it is required in small amounts and is vital for various bodily functions, including the formation of hemoglobin in blood.

5. **Conclusion:**
- Among the given options, the only micronutrient is **Iron (D)**.

**Final Answer: D) Iron**

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