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
[{'content': 'Mood congruent delusion seen in Depression \nSelect and explain. \nA. Delusion of grandeur, B. Delusion of nihilisim, C. Delusional parasitosis, D. Delusion of reference', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Nihilistic delusion is seen severe depression where patient denies the existence of himself & world. Also called as "Cotard syndrome".', 'role': 'assistant'}]