This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: X-RAYS, Subject name: Radiology
[{'content': 'Which has the highest penetration power? \nSelect and explain. \nA. Neutrons, B. Beta rays, C. Gamma rays, D. X-rays', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Neutrons have the highest penetration power. The penetration power in increasing order isAlpha< Beta<Xray<Gamma< Neutron', 'role': 'assistant'}]