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: Pharmacology
[{'content': 'Omeprazole is a \nSelect and explain. \nA. Antihistamine, B. Proton pump inhibitor, C. Ulcer protective, D. Ulcer healing drug', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]