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: Biochemistry
[{'content': 'Which vitamin is related to a co-factor in glycine Metabolism? \nSelect and explain. \nA. V, E, B. Folic acid, C. Thiamine, D. Pantothenic acid', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Tetrahydrofolic acid and S- adenosyl methionine act as a carrier compound for single carbon units.', 'role': 'assistant'}]