This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: CVS Embryology, Subject name: Anatomy
[{'content': 'Which of the following embryonic aerial structures is most likely responsible for the origin of the patent ductus aeriosus? \nSelect and explain. \nA. Right fouh arch, B. Left fifth arch, C. Right fifth arch, D. Left sixth arch', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Proximal pa of 6th arch aery - Pulmonary aery. Distal pa of left 6th arch aery - Ductus aeriosus.', 'role': 'assistant'}]