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: Surgery
[{'content': 'According to Broun "Chemical tourniquet" is: \nSelect and explain. \nA. Adrenaline., B. Hyaluronidase, C. Both, D. None', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Adrenaline was discovered by Albel. Broun suggested using adrenaline as a "Chemical tourniquet" to prolong the duration of local anesthetics.', 'role': 'assistant'}]