This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
[{'content': 'Most potent pain producing neurotransmitter \nSelect and explain. \nA. Acetylcholine, B. Substance P, C. Bradykinin, D. Histamine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Algogens are pain producing substances and Bradykinin is the most potent algogen Ref:Guyton and Hall textbook of medical physiology 12th edition,page number:698,699,700', 'role': 'assistant'}]