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: Microbiology
[{'content': 'Most common cardiac defect seen in Rubella syndrome \nSelect and explain. \nA. Pulmonary stenosis, B. VSD, C. ASD, D. Mitral regurgitation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Most common cardiac defect is PDA followed by PS, followed by VSD.', 'role': 'assistant'}]