This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: FMGE 2018, Subject name: Pharmacology
[{'content': 'In the management of diabetes mellitus, lactic acidosis is caused by which of the following? \nSelect and explain. \nA. Tolbutamide, B. Glipizide, C. Pioglitazone, D. Metformin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Metformin:- S/E: Lactic acidosis Megaloblastic anemia To prevent lactic acidosis, Metformin is to be avoided in high risk patients: Old patients Pt. with renal failure Pt. with liver diseases CHF Tolbutamide (1st gen. Sulfonylureas) - s/e - Hypoglycemia, weight gain. Glipizide (2nd gen. Sulfonylureas) - s/e - Hypoglycemia Pioglitazone - acts by stimulating PPAR-g - reversal of Insulin resistance, s/e - hepatotoxic, edema and Increased risk of urinary bladder cancer', 'role': 'assistant'}]