This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vitamins and Minerals, Subject name: Biochemistry
Which vitamin deficiency causes methylmalonic aciduria? 
Select and explain. 
A. Vitamin B1, B. Vitamin B12, C. Vitamin B6, D. Vitamin B5
B: Vitamin B12
Answer: B: Vitamin B12 
Explanation: Ans. is 'b' i.e., Vitamin B12 * Methylmalonyl-CoA is accumulated and excreted in urine as methylmalonic acid (methylmalonate) in vitamin B12 deficiency, i.e. methylmalonic aciduria.