This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autoimmune skin disorders, Subject name: Dental
[{'content': 'A person came with a unilateral white skin lesion with leukotrichia. Diagnosis is \nSelect and explain. \nA. Segmental vitiligo, B. Piebaldism, C. Albinism, D. Nevus achromicus', 'role': 'user'}, {'content': "Answer: B \nExplanation: Piebaldism is a rare autosomal dominant trait characterized by well-demarcated hypopigmented macules The most typical and common clinical picture is a white forelock often associated with a V-shaped area of leukoderma on mid-forehead Mostly seen over the anterior poion of the limbs, seen on the face paicularly on the chinLesions can be bilateral but not always symmetrical Other features: inter-pupillary distance is increased (Ref: Rook's page 1856 chapter 70.30)", 'role': 'assistant'}]