This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Alcohol, Subject name: Medicine
Wemicke-Korsakoff syndrome is due: 
Select and explain. 
A. Riboflavin deficiency, B. Thiamine deficiency, C. Pyridoxin deficiency, D. Niacine deficiency
B: Thiamine deficiency
Answer: B: Thiamine deficiency 
Explanation: (Thiamine deficiency): Ref: 403-4-H (169,442-HI7th)* Alcoholic patients with chronic thiamine deficiency may also have CNS manifestations known as Wernicke's encephalopathy (consisting of horizontal nystagmus, ophthalmoplegia, cerebellar ataxis, and mental impairment, when there is an additional loss of memory and a confabulatory psychosis, the syndrome is known as Wernicke Korsakoff syndrome.