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': 'Verapamil is not associated with: \nSelect and explain. \nA. Diabetes., B. Constipation., C. Bradycardia., D. Increased PR internal.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Thiazides and beta-blockers are not safe in diabetic patients', 'role': 'assistant'}]