This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Schizophrenia Spectrum and Other Psychotic Disorders, Subject name: Psychiatry
Delusional belief about subjective double is called: 
Select and explain. 
A. Doppelganger, B. Autoscopy, C. Delusion of misidentification, D. Depersonalization
A: Doppelganger
Answer: A: Doppelganger 
Explanation: Doppelganger is the delusional belief that there is a subjective double. Delusion of misidentification are of two types - positive and negative. Negative misidentification is called as Capgras syndrome. Positive misidentification is called as Fregoli's syndrome. Autoscopy is looking oneself externally and knowing it as themselves.