<prompt> Which of the following is a cause of reversible dementia?Subacute combined degeneration.Picks diseaseCreutzfeldt - Jakob disease.Alzheimers disease  <response>: Answer is A Subacute combined degeneration Subacute combined degeneration is caused by vitamin B12 deficiency. Vitamin deficiencies including vitamin B,2 deficiency constitute potentially reversible causes of dementia. 