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': 'Which of the following enzyme activities can be used to help diagnose riboflavin deficiency? \nSelect and explain. \nA. RBC transketolase, B. RBC glutathione reductase, C. Branched chain ketoacid dehydrogenase, D. RBC transaminase', 'role': 'user'}, {'content': 'Answer: B \nExplanation: VITAMIN TEST Thiamine(B1) RBC Trans-ketolase Riboflavin(B2) RBC glutathione reductase Pyridoxine(B6) RBC transaminase Folic acid(B9) FIGLU excretion/Histidine load test Cobalamine(B12) Serum methyl malonate level Reference: Harpers illustrated biochemistry 30th edition', 'role': 'assistant'}]