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: Anaesthesia
[{'content': 'In spinal anesthesia which fibers are affected earliest? \nSelect and explain. \nA. Sensory, B. Motor, C. Sympathetic preganglionic, D. Vibration', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Sympathetic preganglionic REF: Morgan 3rd e p-260 Order of blockade in spinal anesthesia: Autonomic preganglionic > Temperature > Prick > Pain > Touch > Pressure > Motor > Vibration', 'role': 'assistant'}]