Which symptom indicates air pollution damage in plants?

• A. Yellowing across the entire leaf
• B. Purple blotches near the veins
• C. White crust on leaf surfaces
• D. Leaves curling at the edges

Answer: (B)

Air pollution damage in plants often shows up as localized color changes caused by the plant’s stress response. Purple blotches near the veins reflect this targeted reaction, where pigments like anthocyanins accumulate in stressed areas, giving a purplish appearance around the leaf veins. This pattern stands out from other common issues: widespread yellowing usually comes from nutrient problems, a white crust on leaves points to mineral buildup or fungal issues, and curling at the edges is more typical of water stress or heat. So, the purple blotches near the veins are a telltale sign of air pollution damage.