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: Radiology
[{'content': 'Test of choice for Reversible Myocardial Ischemia? \nSelect and explain. \nA. Thallium scan, B. MUGA scan, C. Resting ECHO, D. Coronary angiography', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. Thallium Scan', 'role': 'assistant'}]