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: Pathology
[{'content': 'Bradykinin is a clevage product of - \nSelect and explain. \nA. Kininogen, B. Prekallikrein, C. Kallikrien, D. Histamine', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Kininogen", 'role': 'assistant'}]