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': 'A 6 year old female child reported with a chief complaint of proclined upper anteriors. Parents give a history of prolonged bottle-feeding and a persistent thumb sucking habit. Clinical examination reveals anterior open bite with proclined upper anterior and retroclined lower anterior teeth and associated tongue thrusting.\nUsually digit sucking habits are outgrown by: \nSelect and explain. \nA. 6-7 years, B. 3-4 years, C. 1-2 years, D. 11-12 years', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Thumb-sucking in children\xa0\n\nNo active intervention regardless of type and severity of malocclusion because of general emotional immaturity.\nMost children out grow the habit by approximately 5 years of age.\nMalocclusion is self-correcting, if ceased by the time of eruption of permanent teeth.\nParents are advised to ignore habit.\nGive more attention to the child when not sucking.\nIf occlusion Class II, advise need for future orthodontic treatment.\n\nRef: Textbook of Orthodontics Gurkeerat Singh Second edition', 'role': 'assistant'}]