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': "Well's grading of puimonary embolism is based ona) Dopplerb) Clinical symptomsc) Hemoptysisd) Heart Rate > 100 beats per min \nSelect and explain. \nA. abc, B. acd, C. ac, D. bcd", 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]