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: Unknown
[{'content': 'Marker of Melanoma: \nSelect and explain. \nA. S100, B. Ck 20, C. MTLF, D. Vimentin', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (Rook’s Textbook of Dermatology 7thedition)\n(Refer: Robbins Pathologic Basis of Disease, 8thedition, pg no: 1171-1175)', 'role': 'assistant'}]