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
Which of the following is not true in vitamin B9 deficiency 
Select and explain. 
A. Vitamin B9 is stored in liver for 3 - 4 months, B. Deficiency manifests as increased homocysteine and normal methylmalonic acid levels., C. Deficiency manifests as increase in both homocysteine and methylmalonic acid levels., D. Phenytoin intake can cause deficiency state of Vitamin B9
C: Deficiency manifests as increase in both homocysteine and methylmalonic acid levels.
Answer: C: Deficiency manifests as increase in both homocysteine and methylmalonic acid levels. 
Explanation: Vitamin B9 (folic acid) deficiency result in increased homocysteine level but methylmalonic acid level will be normal.