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: Orthopaedics
[{'content': 'A patient developed breathlessness and chest pain, on second postoperative day after a total hip replacement. Echo-cardiography showed right ventricular dilatation and tricuspid regurgitation.What is the most likely diagnosis - \nSelect and explain. \nA. Acute MI, B. Pulmonary embolism, C. Hypotensive shock, D. Cardiac tamponate', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Onset of chest pain and breathlessness, together with echocardiographic evidence of right ventricular dilatation and tricuspid regurgitation after a high risk procedure (for thromboembolism) like total hip replacement suggests a diagnosis of pulmonary embolism.', 'role': 'assistant'}]