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': 'The phase of cell cycle, most sensitive to radiation isa) M Phase  b) G2Phase  c) S Phase  d) Early G1 Phase e) G0Phase \nSelect and explain. \nA. ac, B. ab, C. de, D. cd', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Cells are most radiosensitive in late G, and early M phase\xa0→\xa0especially G2M interphase.', 'role': 'assistant'}]