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: Unknown
Which of the following attains adult size before birth? 
Select and explain. 
A. Ear Ossicles, B. Maxilla, C. Mastoid Process, D. Parietal bone
A: Ear Ossicles
Answer: A: Ear Ossicles 
Explanation: Ans is 'a' i.e. Ear Ossicles Its an indirect repeat from May 2009 paper."The tympanic cavity and mastoid antrum, auditory ossicles, and structures of the internal ear are all almost fully developed at birth and subsequently alter little. " -Gray's 40/e p623