This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous system, Subject name: Physiology
[{'content': 'Fibers more susceptible to hypoxia are: \nSelect and explain. \nA. Preganglionic, B. Postganglionic, C. Both, D. None', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Preganglionic nerve fibers are more susceptible to hypoxia Ref:Guyton and Hall textbook of medical physiology 12th edition ,pag number:72,73', 'role': 'assistant'}]