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: Surgery
[{'content': 'Pierre Robbin syndrome is - \nSelect and explain. \nA. Cleft palate with syndactly, B. Cleft palate with mandibular hypoplasia and respiratory obstruction, C. Cleft lip with mandibular hypoplasia, D. Cleft lip', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Pierre Robbin syndrome comprises\n\nisolated cleft palate\nretrognathia (posteriorly displaced mandible)\nglossoptosis (posteriorly displaced tongue)\nearly respiratory & feeding difficulties', 'role': 'assistant'}]