This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
[{'content': 'Eustachian tube passes between: \nSelect and explain. \nA. Superior and middle constrictors, B. Above superior constrictor, C. Middle and inferior constrictor, D. Below inferior constrictor', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Eustachian tube passes through sinus of Morgagni, which is a gap between the base of skull and the upper concave border of\xa0superior constrictor muscle.', 'role': 'assistant'}]