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: ENT
[{'content': 'The site of lodging foreign body in the esophagus is - \nSelect and explain. \nA. Upper constrictor, B. Bifurcation of trachea, C. Aortic body, D. Lower esophagus', 'role': 'user'}, {'content': 'Answer: A \nExplanation: By far the most common site is at or just above the cricopharyngeal sphincter (upper constrictor).', 'role': 'assistant'}]