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': 'Velocity of conduction for A- alfa nerve fibers is m/second \nSelect and explain. \nA. 80, B. 70, C. 90, D. 120', 'role': 'user'}, {'content': 'Answer: D \nExplanation: A - alfa fibers are myelinated and have large diameter They have high conduction velocity -120m/second Ref:Guyton and Hall textbook of medical physiology 12th edition,page number: 73', 'role': 'assistant'}]