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: Medicine
[{'content': 'The most common site of esophageal adenocarcinoma is: \nSelect and explain. \nA. Upper 1/3rd, B. Middle 1/3rd, C. Lower 1/3rd, D. Upper 2/3rd', 'role': 'user'}, {'content': "Answer: C \nExplanation: Answer is C (Lower 1/3rd) The most common site of adenocarcinoma esophagus is the lower 1/3rd of esophagus Esophageal Adenocarcinoma invariably arises from Barret's esophagus (Barret's ulcer) which is characteristically located in the distal esophagus around the gastroesophageal junction.", 'role': 'assistant'}]