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: Anatomy
[{'content': 'Which of the following is formed of elastic cailage? \nSelect and explain. \nA. Auditory tube, B. Nasal septum, C. Aicular cailage, D. Costal cailage', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Auditory tubeREF: Basic histology, Carlos & Jose, 11th edition, Chapter 7, Cailage, Textbook of human histology 4th e p. 92-94', 'role': 'assistant'}]