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
FIGLU Test is used for deficiency of ? 
Select and explain. 
A. Vitamin B12, B. Riboflavin, C. Niacin, D. Folic acid
D: Folic acid
Answer: D: Folic acid 
Explanation: Ans. is 'd' i.e., Folic acid