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': 'Continuous murmur is found in \nSelect and explain. \nA. AS combined with AR, B. Systemic A V fistula, C. PDA with reversal f shunt, D. All', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Answer is B (Systemic A V fistula) Aoopulmonary window, systemic AV fistula and ruptured sinus of valsalva are associated with continuous murmurs caused by high to low pressure shunting of blood.', 'role': 'assistant'}]