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: Dental
[{'content': "According to Mahler's theory, period of normal symbiotic phase is: \nSelect and explain. \nA. 0 - 1 year, B. 4 weeks to 4 years, C. 8 weeks to 8 years, D. 5 to 36 months", 'role': 'user'}, {'content': "Answer: B \nExplanation: According to Mahler's theory:\n\nThe normal autistic phase is 0-1 year.\nNormal symbiotic phase is 4 weeks to 4 years.\nSeparation individualization phase is 5 to 36 months.", 'role': 'assistant'}]