This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'Which of the following attains adult size before bih? \nSelect and explain. \nA. Ear ossicles, B. Maxilla, C. Mastoid process, D. Parietal bone', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The ossicles of the middle ear fully ossify in the fouh month of intrauterine lifeThey are the first bones in body to do soRef: Inderbir Singh&;s Human embryology; Tenth edition; Pg 368', 'role': 'assistant'}]