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': 'Wide fixed S2 is seen in __________ \nSelect and explain. \nA. ASD, B. VSD, C. PDA, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Widely split S2 seen in ASD. Ghai essential of pediatrics, eighth edition, p.no:413', 'role': 'assistant'}]