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: Unknown
Site for placing an electrode in auditory brain stem Implant is: 
Select and explain. 
A. Sinus tympani, B. Recess of fourth ventricle, C. Round window, D. Lateral ventricle
B: Recess of fourth ventricle
Answer: B: Recess of fourth ventricle 
Explanation: Ref. Diseases of Ear, Nose and Throat. Pg 127
 
Auditory brainstem implants have three main parts:

A microphone and sound processor positioned behind the ear to pick up sounds
A decoding chip placed under the skin to transmit information picked up by the microphone
Electrodes connected directly to the brainstem(4th ventricle recess), when stimulated, alert you to sound