Which trio are the primary nutrients for plants?

• A. Nitrogen, Phosphorus, and Potassium
• B. Calcium, Magnesium, and Sulfur
• C. Nitrogen, Potassium, and Calcium
• D. Phosphorus, Potassium, and Magnesium

Answer: (A)

Plants rely on essential nutrients, and among them three are required in the largest amounts, known as primary nutrients: nitrogen, phosphorus, and potassium. These macronutrients support different aspects of growth—nitrogen fuels leafy growth and general metabolism, phosphorus promotes root and flower development and energy transfer, and potassium helps overall vigor, water regulation, and resilience. That’s why this trio is the best answer for identifying the primary nutrients. The other options mix in secondary nutrients (like calcium, magnesium, and sulfur) or omit one of the primary nutrients, so they don’t represent the main trio. In fertilizers, the N-P-K labeling reflects these three key nutrients.