This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gastrointestinal tract, Subject name: Pharmacology
[{'content': 'A patient presents with zo11inger-Ellison syndrome due to gastrinoma. He has two bleeding ulcers and diarrhoea. A drug that irreversibly inhibits the H+/K+ ATPase in gastric parietal cells is: \nSelect and explain. \nA. Cimetidine, B. Cisapride, C. Glycopyrrolate, D. Omeprazole', 'role': 'user'}, {'content': 'Answer: D \nExplanation: that react covalently with SH groups of the H+K+ATP ase enzyme and inactivate it irreversibly ESSENTIALS OF MEDICAL PHARMACOLOGY SEVENTH EDITION KD TRIPATHI PG NO 651', 'role': 'assistant'}]