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
Vitamin B12 deficiency has A/E 
Select and explain. 
A. Folate trap, B. Decreased methyl malonyl CoA, C. SACD, D. Megaloblastic anemia
B: Decreased methyl malonyl CoA
Answer: B: Decreased methyl malonyl CoA 
Explanation: B i.e. Decreased methylmalonyl CoA