This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Acne and chemical peeling, Subject name: Dental
[{'content': 'Chemical peeling is indicated in all of the following except \nSelect and explain. \nA. Acne vulgaris, B. Lichen planus, C. Melasma, D. Phtotoaging', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Chemical peeling is indicated in Melasma, Acne, Acne scars and Photo ageing Chemical peels act by a. Skin resurfacing b. Collagen remodelling Thus they help is removal of scars/ pigmentation', 'role': 'assistant'}]