Symptom of which nutrient deficiency appear first on older leaves and then advance up the stem to younger leaves

Explanation

The correct option is (a) Nitrogen Deficiency. Nitrogen deficiency symptoms often appear first on older leaves and then progress upward to affect younger leaves. This pattern is because nitrogen, being a mobile nutrient in plants, is easily translocated within the plant from older to younger tissues. When nitrogen is deficient, the plant prioritizes the allocation of available nitrogen to younger, actively growing tissues, resulting in the symptoms manifesting initially in older leaves.