This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Paranasal Sinuses, Subject name: ENT
Which of the following is not a pneumatic bone: 
Select and explain. 
A. Ethmoid, B. Sphenoid, C. Maxillary, D. Mandible
D: Mandible
Answer: D: Mandible 
Explanation: Pneumatic bones are those bones which contain an air filled cavity within them which make them light in weight. In humans, they are seen in relation to nasal cavity & enclose paranasal sinuses. Besides making the skull light in weight they also help in resonance of sound & act as air conditioning chambers for inspired air. Pneumatic bones are - maxilla, frontal bone, sphenoid, ethmoid and Mastoid