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': 'Esomeprazole acts by inhibiting: \nSelect and explain. \nA. H+K+ ATPase pump, B. H+Na+ ATPase pump, C. H+ pump, D. Any of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Esmoprosol is an example of proton pumb inhibitor ESSENTIALS OF MEDICAL PHARMACOLOGY SEVENTH EDITION KD TRIPATHI PG NO.653', 'role': 'assistant'}]