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
Velocity of conduction for A- alfa nerve fibers is m/second 
Select and explain. 
A. 80, B. 70, C. 90, D. 120
D: 120
Answer: D: 120 
Explanation: 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