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: ENT
Cochlear implant is done if the following is intact: 
Select and explain. 
A. Outer hair cell, B. Inner hair cell, C. Spiral ganglion cell, D. Auditory nerve
D: Auditory nerve
Answer: D: Auditory nerve 
Explanation: They are indicated for patients of profound binaural SNHL (with non functional cochlear hair cells) who have intact auditory nerve functions and show little or no benefit from hearing aids.