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: Medicine
[{'content': 'In stable angina - \nSelect and explain. \nA. CK-MB is elevated, B. Troponin I is elevated, C. Myoglobin is elevated, D. The levels of cardiac markers remain unchanged', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]