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
Delusion of doubles is found in - 
Select and explain. 
A. Schizo affective disorder, B. Capgras syndrome, C. Reactive psychosis, D. Paranoid schizophrenia
B: Capgras syndrome
Answer: B: Capgras syndrome 
Explanation: Capgras syndrome is delusional disorder, where a person believes that his family member has been kidnapped and replaced by a stranger.