Which of the following would be the most appropriate treatment for rehabilitation of a patient who has bilateral profound deafness following surgery for bilateral acoustic schwannoma -
"The auditory brainstem implant is designed to restore some hearing to patients lacking functionally intact cochlear nerves, such as in patients with bilateral vestibular schwannoma" 

In this situation, the cochlear implant will not be helpful. You can easily understand this; cochlear implant stimulates VIIIth nerve directly, however in acoustic neuroma pathology lies within the VIIIth nerve, so it will not be able to transmit the signals forward after stimulation by cochlear implants.
On the other hand, brain stem implant directly stimulates the cochlear nucleus complex in the brainstem. Therefore, a brain stem implant is the device of choice.
Bilateral with powered digital hearing AID
Bilateral cochlear implants
Unilateral cochlear implant
Brain stem implant