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': 'Mature swallow pattern is characterized by all of the following, except: \nSelect and explain. \nA. Relaxation of lips, B. Placement of tongue behind the maxillary incisors, C. Placement of the mandible until posterior teeth are in contact, D. Relaxation of the elevator muscles of mandible', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Humans show 2 types of swallow patterns:\n\nInfantile and neonates swallow\nMature/adult swallow.\n\nInfantile swallow\xa0 is characterized by:\n\nActive contractions of the lip muscles.\nTongue is placed between the gum pads and tongue tip is brought forward into contact with the lower lip.\nLittle posterior tongue activity /pharyngeal muscle activity.\nTongue-to-lower lip posture adopted by infants at rest.\nContraction of lips and facial muscles helps to stabilize the mandible.\nVigorous mandibular thrust.\n\nPhysiologic transition of swallow begins during the 1st year of life and continues for several years. Mature swallow is seen usually by 4-5 years. Maturation of swallow pattern occurs with the addition of semisolid and solid food to the diet. Increasing activation of the elevator muscles of mandible is seen. When sucking activity stops, a continued transition of swallow leads to acquisition of adult pattern of swallow.\nThis swallow is characterized by:\n\nCessation of lip activity, i.e, lips relaxed.\nPlacement of tongue tip against the palate and behind upper incisors.\nPosterior teeth into occlusion during swallow.\nDownward and forward mandibular growth increases intraoral volume and vertical growth of the alveolar process changes tongue posture.\nMandible stabilized by contraction of muscles of mastication.\n\nRef: Textbook of orthodontics 2nd ed Gurkeerat Singh page no 595,596', 'role': 'assistant'}]