This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'Cells are most radiosensitive in \nSelect and explain. \nA. S phase, B. Mphase, C. G1 phase, D. G0 phase', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ref Robbins9/e p140 Cells are most radiosensitive in G2M interphase Cells are least radioactive in Sphase', 'role': 'assistant'}]