This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'The ductus aeriosus is derived from the following aoic arch \nSelect and explain. \nA. 3rd, B. 4th, C. 5th, D. 6th', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The pa of the left sixth arch aery, between the branch to the lung bud and aoa,forms the ductus aeriosus HUMAN EMBRYOLOGY-INDERBIR SINGH TENTH EDITION-PAGE NO:255', 'role': 'assistant'}]