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: Pathology
[{'content': 'Leiomyoma is a tumor of \nSelect and explain. \nA. cerebral tissue, B. smooth muscle, C. striated muscle, D. cardiac muscle', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]