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: Physiology
[{'content': 'Sensory fiber with least conduction velocity:September. 2005 \nSelect and explain. \nA. C- fiber, B. Alpha fiber, C. beta fiber, D. Gamma fiber', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. A: C- fiberAlpha fibers are the thickest (fiber diameter of 12-20 micrometer) and fastest conduction velocity (of 70-120 mis) whereas C-fibers are the thinnest (fiber diameter of 0.3-1.2 micrometer) and slowest conduction velocity (of 0.5-2 m/s)', 'role': 'assistant'}]