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: Medicine
[{'content': 'Clinical finding inAV fistula is one of the following \nSelect and explain. \nA. Pericarditis, B. Sinus tachycardia, C. Cardiac arryhthrnia, D. Hypothermia', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]