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': 'Which of the following decreases effectiveness of insulin - \nSelect and explain. \nA. Thiazide, B. Atropine, C. b-blockers, D. Acute alcohol ingestion', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Thiazide o Thiazide, furosamide, coicosteroids, oral contraceptives, salbutamol, nifedipine tend to raise blood sugar and reduce effectiveness of insulin.", 'role': 'assistant'}]