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: Anatomy
[{'content': 'Chorda tympani contain: \nSelect and explain. \nA. Preganglionic sympathetic fibres, B. Preganglionic parasympathetic fibres, C. Postganglionic sympathetic fibres, D. Postganglionic parasympathetic fibres', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]