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': 'Which of the following is the most ionizing radiation – \nSelect and explain. \nA. Alpha, B. Beta, C. X-rays, D. Gamma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Alpha rays have maximum ionizing potential', 'role': 'assistant'}]