This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Surgery
[{'content': 'Hyperophic pyloric stenosis what to be normalized before surgery \nSelect and explain. \nA. Potassium, B. Bicarbonate, C. Calcium, D. Water', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Due to severe vomiting, there will be hypochloraemic, hyponatremic, hypokalemic, hypomagnesemic metabolic alkalosis, so we have to correct alkalosis by if bicarbonate. SRB edition :5 page: 829', 'role': 'assistant'}]