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: Pediatrics
[{'content': 'Which is going to best declare the case as that of interatrial septal defect with other cardiac abnormalities - \nSelect and explain. \nA. Elevated pressurein left atrium, B. Elevated pressure in right atrium, C. Elevated PO, in pulmonary aery, D. Systolic murmur', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Elevated pressure in left atrium", 'role': 'assistant'}]