This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'Most common casue of acute RVF- \nSelect and explain. \nA. Massive pulmonary embolism, B. Tricuspid stenosis, C. Pulmonary stenosis, D. Tricuspid regurgitation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: pulmonary hypeension and massive pulmonary embolism are the most impoant cause of acute RVF Ref Davidson 23rd edition pg 478', 'role': 'assistant'}]