which one of the following nutrients is not available in fertilisers?

Options

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

Explanation

**Step-by-Step Solution:**

1. **Understanding Fertilizers:**
- Fertilizers are synthetic chemicals added to crops to enhance soil fertility and increase crop yield.

2. **Identifying Nutrients in Fertilizers:**
- Common nutrients found in fertilizers include nitrogen, phosphorus, and potassium. These nutrients are essential for plant growth.

3. **Analyzing the Options:**
- The question provides four options: nitrogen, phosphorus, iron, and potassium.
- We need to determine which of these nutrients is not typically found in fertilizers.

4. **Recognizing the Role of Iron:**
- Iron is an essential nutrient for plants, but it is primarily absorbed from the soil rather than supplied through fertilizers.

5. **Conclusion:**
- Since nitrogen, phosphorus, and potassium are present in fertilizers, the nutrient that is not available in fertilizers is **iron**.

**Final Answer:**
- The nutrient that is not available in fertilizers is **iron**.

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