This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Pharmacology
[{'content': 'Nitrates can be used for all of the following conditions except \nSelect and explain. \nA. Congestive hea failure, B. Cyanide poisoning, C. Esophageal spasm, D. Renal colic', 'role': 'user'}, {'content': 'Answer: D \nExplanation: nitrates are used in CHF Angina pectoris Myocardial infarction Biliary colic Diffuse esophageal spam Cyanide poisoning Refer kDT 6/e p 527', 'role': 'assistant'}]