This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Radiotherapy Pa 2, Subject name: Radiology
[{'content': 'The most radiosensitive phase of cell cycle is: \nSelect and explain. \nA. G2M interface, B. G2, C. S, D. M', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Radiosensitivity of the cell cycle pahses : G2M > M > G2> G1> S. G2M is most Radiosensitive phase and S phase is most radioresistant phase', 'role': 'assistant'}]