This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
True about central nystagmus is 
Select and explain. 
A. Changing direction, B. Not suppressed by optic fixation, C. Horizontal or veical, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Nystagmus is central when the lesion is in the central neural pathways. It cannot be suppressed by optic fixation. The direction of nystagmus is changing and is non-fatiguable. (Ref: Diseases of EAR, NOSE AND THROAT by PL DHINGRA - 6th Edition)