This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: DNA Replication , Subject name: Biochemistry
[{'content': 'DNA replication occurs in which phase of cell cycle? \nSelect and explain. \nA. G1 phase, B. S phase, C. G2 phase, D. M phase', 'role': 'user'}, {'content': 'Answer: B \nExplanation: ANSWER: (B) S phaseREF: Ganong\'s physiology 22nd ed chapter 1"S or synthetic phase of cell cycle is the one in which replication of DNA OCCURS.', 'role': 'assistant'}]