This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Major Depression, Subject name: Psychiatry
[{'content': 'Nihilistic delusions seen in: (Repeat) \nSelect and explain. \nA. Depression, B. Mania, C. Schizophrenia, D. OCD', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans: A (Depression) Ref: Kaplan & Sadock's Synopsis of Psychiatry. 10th editionExplanation:Delusion is one of the psychotic symptoms seen in several disorders (see previous question).Delusion is false, unshakable belief held with extraordinary conviction.Nihilistic delusion is a type of delusion, characterized by a false belief that everything will come to an end including one's life or lost everything including one's body parts.It is seen in severe depression.Hypochondriac delusion is a false belief that one has an incurable illness.Cotrad syndrome: Presence of both nihilistic and hypochondriac delusions, seen in severe depression. Other delusions seen in depression are:Delusion of hopelessness/helplessness/ worthlessness.Delusion of guilt (marker of suicidality).Mania - Delusion of grandiositySchizophrenia - Bizarre delusions, delusion of persecution/reference.", 'role': 'assistant'}]