This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of nucleic acids, Subject name: Biochemistry
[{'content': 'Total number of molecules of ATP required for denovo purine synthesis? \nSelect and explain. \nA. 2, B. 5, C. 6, D. 4', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Reference: Harpers illustrated biochemistry 30th edition', 'role': 'assistant'}]