This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous System, Subject name: Radiology
Marchiafava-Bignami diseaseis characterized by? 
Select and explain. 
A. Callosal atrophy, B. Cerebellar atrophy, C. Brainstem atrophy, D. Cerebral peduncular atrophy
A: Callosal atrophy
Answer: A: Callosal atrophy 
Explanation: Ans AIt is a rare CNS disorder associated with chronic alcoholism or malnutrition. On imaging there is corpus callosal atrophy and demyelination.Sandwich sign and ears of lynx sign maybe seen.