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: ENT
[{'content': 'Choana is - \nSelect and explain. \nA. Anterior nares, B. Posterior nares, C. Tonsils, D. Larynx', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Internal nose is divided into right and left nasal cavities by nasal septum.\nEach nasal cavity communicates with the exterior through nares or nostrils and with nasopharynx through posterior nasal aperture or posterior nares or choana.', 'role': 'assistant'}]