The inner ear is the location where fine changes in sound pressure in the environment are translated into neural signals. The inner ear is the most inner most part of the vertebrate ear. It is mainly responsible for sound detection and balance. It consists of the bony labyrinth, a hollow cavity in the temporal bone of the skull with a system comprising of two main functional parts (cochlea and the vestibular system).
I would say b and a don't quote me if I'm wrong :P
Species 3&5 because they have the lowest number
The answer is cell reproduction
