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
True about A- delta fibers 
Select and explain. 
A. Associated with slow pain, B. Associated with fast pain, C. Both, D. None
B: Associated with fast pain
Answer: B: Associated with fast pain 
Explanation: A-delta fibers are associated with fast pain They are myelinated but conduction velocity is least among A fibers. Ref:Guyton and Hall textbook of medical physiology 12th edition,page number: 73