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: Unknown
[{'content': 'Which of the following is an example of intellectual disability? \nSelect and explain. \nA. Dyslexia, B. ADHD, C. Autistic spectrum disorder, D. Mental retardation', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ref. Oxford textbook of Psychiatry. Page. 488', 'role': 'assistant'}]