This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax, Subject name: Anatomy
[{'content': 'A 2-day-old newborn male develops mild cyanosis. An ultrasound examination reveals a patent ductus arteriosus. Which of the following infections will most likely lead to this congenital anomaly? \nSelect and explain. \nA. Toxoplasmosis, B. Rubella, C. Cytomegalovirus, D. Varicella virus', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Congenital heart defects are common problems that can be caused by teratogens, such as the rubella virus, or single-gene factors or chromosomal abnormalities.', 'role': 'assistant'}]