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
According to the the National Trust Act, patients suffering from which of the following disease as per ICD 10 or DSM IV criteria are eligible for disability benefit? 
Select and explain. 
A. Dementia, B. Schizophrenia, C. Chronic Pain Syndrome, D. Mental retardation
D: Mental retardation
Answer: D: Mental retardation 
Explanation: Among the options given in the question patients suffering from mental retardation is eligible for disability benefit as per National Trust Act, 1999. Schizophrenia and Bipolar Disorder are mental disorders which are not considered as a permanent disability. Ref: Psychological Implications of Information Technology By N. K. Chandel, Page 154