This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Embryology, Subject name: Anatomy
[{'content': 'Arch of aorta develops from: \nSelect and explain. \nA. Right 4th aortic arch, B. Left 4th aortic arch, C. Right 6th aortic arch, D. Left 6th aortic arch', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B. Left 4th aortic archThe aortic arch is the connection between the ascending and descending aorta, and its central part is formed by the left 4th aortic arch during early development', 'role': 'assistant'}]