This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: vitamins, Subject name: Biochemistry
[{'content': 'Vitamin B12 is essential in what aspect of blood cell reproduction? \nSelect and explain. \nA. Formation of hemoglobin, B. Extrusion of the nucleus from the normoblasts, C. Formation of DNA, D. Activation of erythropoietin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Within 6-9 hours of treatment with vitamin B12 formation of nuclear DNA component promotes normoblastic reaction of the bone marrow Folic acid also promotes the formation of nucleic acids. Ref: Biochemistry by U. Satyanarayana 3rd edition Pgno : 154', 'role': 'assistant'}]