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: Pediatrics
[{'content': 'In atrial septal defect the aoa is \nSelect and explain. \nA. Small, B. Normal, C. Enlarged, D. Aneurysmal', 'role': 'user'}, {'content': 'Answer: A \nExplanation: In ASD chest xray shows small aoic shadow. Ref : Ghai essential of pediatrics,eighth edition, P.no: 413', 'role': 'assistant'}]