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': 'An absolute contraindication of MRI is – \nSelect and explain. \nA. Pacemaker, B. Prosthetic cardiac valves, C. Insulin pump, D. Choclear implants', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Cardiac pacemakers are generally considered as an absolute contraindication.\nProsthetic cardiac valves, insulin pump and coclear implants are relative contraindications', 'role': 'assistant'}]