This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
[{'content': 'S 100 is a marker of ?- \nSelect and explain. \nA. Melanoma, B. Schwannoma, C. Histiocytoma, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Harshmohan textbook of pathology 7th edition. immunohistochemical stain for melanoma, schwannoma, histiocytoma is S 100. .', 'role': 'assistant'}]