This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
[{'content': 'A male is presenting with a violaceous papule which is pruritic. There is pterygium of nail with cicatracial alopecia. Diagnosis is – \nSelect and explain. \nA. Psoriasis, B. Pityriasis rosea, C. Lichen planus, D. Seborrheic dermatitis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Information we got :-\n\n\nLesion is pruritic\nNo scales\nViolaceous papule\nPterygium of nail\nCicatracial alopecia\n\n\nAll are seen in Lichen planus.', 'role': 'assistant'}]