Which nutrient is required for photosynthesis and formation of oils, starches, and sugars, and encourages flowering and root formation?

• A. Potassium
• B. Magnesium
• C. Phosphorus
• D. Nitrogen

Answer: (C)

Phosphorus is essential for how plants manage energy and build key compounds. It’s a component of ATP and other high‑energy molecules that drive the energy‑requiring steps of photosynthesis and carbohydrate metabolism, which is why it’s linked to the formation of oils, starches, and sugars. Phosphorus also supports reproductive development and root formation, helping plants produce flowers and develop a strong root system. While other nutrients support related roles (magnesium with chlorophyll, nitrogen with proteins and growth, potassium with enzyme activity and water balance), phosphorus uniquely aligns with energy transfer, carbohydrate formation, and root/flower development.