Deficiency symptom of which of the following nutrient first appear on older or lower leaves?

Correct option is E

Deficiency symptoms of potassium first appear on older or lower leaves of a plant. Potassium is a macronutrient essential for various physiological processes in plants, including enzyme activation, osmoregulation, and the synthesis of carbohydrates and proteins. When a plant experiences a deficiency in potassium, it tends to mobilize this nutrient from older leaves to younger tissues, leading to symptoms primarily appearing in the older leaves.