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': 'Which of the following is used to measure pain intensity \nSelect and explain. \nA. Visual analog scale, B. Visual anaesthesia score, C. Verifiable assessment of soreness, D. Visual assessment of soreness', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]