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': 'Helicobacter pylori is found in greatest number in: \nSelect and explain. \nA. Oesophagus, B. Gastric Antrum, C. Caecum, D. Oral cavity', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]