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 drugs is capable of maintaining blood levels for 24 hours after a single administration but has useful antianginal effects lasting only about 10 hours ? \nSelect and explain. \nA. Amyl nitrite, B. Isosorbide mononitrate, C. Nitroglycerine (sublingual), D. Nitroglycerine (transdermal)', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]