This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lichen planus and Other papulosquamous disorders, Subject name: Dental
[{'content': 'A patient presented with scarring alopecia, thinned nails, hyperpigmented macular lesions over the trunk and oral mucosa. Diagnosis is: \nSelect and explain. \nA. Psoriasis, B. Leprosy, C. Lichen planus, D. Pemphigus', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Scarring alopecia is found in LP and Leprosy both. But oral mucosal involvement and thinning of nails or the diagnosis of LP.', 'role': 'assistant'}]