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': 'Technitium 99 is most commonly used in \nSelect and explain. \nA. Cardiology, B. Radiotherapy, C. Radiodiagnosis, D. Nuclear medicine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: RADIO NUCLIDE IMAGING 99Tc is the most commonly used radiopharmaceutical, for imaging in nuclear medicine.', 'role': 'assistant'}]