This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anatomy of Skin, Subject name: Skin
[{'content': 'Comedones are seen in : \nSelect and explain. \nA. Pityriasis, B. Lichen planus, C. Adenoma sebaceum, D. Acne vulgaris', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans is 'd' Acne vulgaris Primary lesion of Acne Vulgaris is comedonesOpen comedones are Black Heads*Closed comedones are White Heads*Comedones can evolve intoPapulesPustules &CystsSite of Appearance (requires presence of Sebaceous gland)Face (MC)*ShoulderBack & Upper chest", 'role': 'assistant'}]