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: Surgery
[{'content': 'The most frequent symptom of gastric diverticulum is \nSelect and explain. \nA. Epigastric pain, B. Haematemesis, C. Vomiting, D. Pain relieved by food', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]