The main nutrients present in fertilisers are nitrogen, phosphorus and :

Options

A. Potassium
B. Argon
C. Chlorine
D. Hydrogen

Answer

**Step-by-Step Solution:**

1. **Identify the Main Nutrients in Fertilizers**: The question asks for the main nutrients found in fertilizers. The commonly known primary nutrients are nitrogen (N) and phosphorus (P).

2. **Consider the Options**: The question likely provides multiple-choice options. Among these options, we need to identify the third main nutrient that is commonly found in fertilizers alongside nitrogen and phosphorus.

3. **Recall the Third Nutrient**: The third main nutrient that is often included in fertilizers is potassium (K). Therefore, the complete set of primary nutrients in fertilizers is nitrogen, phosphorus, and potassium.

4. **Conclusion**: Based on the information gathered, the answer to the question is potassium.

**Final Answer**: The main nutrients present in fertilizers are nitrogen, phosphorus, and potassium.

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