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
Not a pa of bony labyrinth? 
Select and explain. 
A. Cochlea, B. Vestibule, C. Utricle, D. Semicircular canal
C: Utricle
Answer: C: Utricle 
Explanation: The inner ear within the petrous pa of temporal bone consists of a membranous labyrinth enclosed in a bony (osseous) labyrinth. So, inner ear has two pas : ? 1) Bony labyrinth :- Cochlea, Vestibule, Semicircular canals. 2) Membranous labyrinth :- Cochlear duct, utricle, Saccules, three semicircular ducts, and endolymphatic duct & sac.