This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Organic mental disorders, Subject name: Psychiatry
Which of the following behavioural problems would suggest an organic brain lesion 
Select and explain. 
A. Formal thought disorder, B. Auditory hallucinations, C. Visual hallucinations, D. Depression
C: Visual hallucinations
Answer: C: Visual hallucinations 
Explanation: Visual hallucinations are more common in acute organic states with clouding of consciousness than in functional psychosis. Visual hallucinations are extremely rare in schizophrenia, so much so that they should raise a doubt about the diagnosis. Fish's Clincal Psychopathology 3rd edition, pages 23,24.