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: Psychiatry
One of the following is a reversible cause of dementia : 
Select and explain. 
A. Toxic dementia, B. Alzheimer's ds., C. Multi - infarct dementia, D. Pick ds
A: Toxic dementia
Answer: A: Toxic dementia 
Explanation: A i.e. Toxic