- A Nitrogen
- B Sulfur
- C Potassium
- D Phosphorus
Correct answer: D. Phosphorus
Explanation: Phosphorus is a key component of ATP (energy), DNA/RNA (genetic material), and phospholipids (cell membranes). Deficiency causes poor root growth, purple discoloration of leaves, and delayed maturity.
Concept context
Essential mineral elements, their roles and deficiency symptoms. Nitrogen fixation and soil nutrition.