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': 'Which of the following carries fast pain: \nSelect and explain. \nA. A-alfa, B. A-delta, C. B, D. C', 'role': 'user'}, {'content': 'Answer: B \nExplanation: A-delta fibers are associated with fast pain They are myelinated Ref:Guyton and Hall textbook of medical physiology 12th edition,page number:73', 'role': 'assistant'}]