A chronic alcoholic presents with Wernicke-Korsakoff syndrome, characterized by confusion, ataxia, and nystagmus. This condition is primarily due to a deficiency in which vitamin?

✓ Correct Answer: Option A

Thiamine (Vitamin B1) is a crucial cofactor for several enzymes in glucose metabolism, especially in the brain. Chronic alcohol abuse impairs thiamine absorption and utilization, leading to Wernicke-Korsakoff syndrome.