This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pharyngeal Arches, Subject name: Anatomy
[{'content': 'Embryological dorsal aoa forms: \nSelect and explain. \nA. Ascending aoa, B. Descending aoa, C. Common carotid aery, D. Pulmonary trunk', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Embryological dorsal aoa forms distal pa of descending aoa. Proximal pa of descending aoa develops from Left dorsal aoa distal to attachment of fouh arch aery and Distal pa from fused dorsal aoae forming single median aery. Ascending aoa and pulmonary trunk develops from truncus aeriosus (a pa of hea tube). Arch of aoa develops from 4th arch aery. Common carotid aery develop from aoic arch III.', 'role': 'assistant'}]