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': 'Which of the following chemicals or isotopes is used in cardiac ventriculography? \nSelect and explain. \nA. Technetium, B. Gallium, C. Lipodate, D. Diatrizoate', 'role': 'user'}, {'content': 'Answer: A \nExplanation: 99m Technitium is used as an isotope in Cardiac Ventriculography. It is a medical imaging technique used to detemine the cardiac functions. Ejection fraction, stroke volume and cardiac output can be measured by the procedure. Gallium is used to find out places where inflammation is present.', 'role': 'assistant'}]