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
Glutathione reductase assay is helpful in assessing the deficiency of 
Select and explain. 
A. Niacin, B. Vit B5, C. Pyridoxine, D. Riboflavin
D: Riboflavin
Answer: D: Riboflavin 
Explanation: None