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: Ophthalmology
Disscociated vertical deviation seen in 
Select and explain. 
A. Vertical on looking up, B. Horizontal on looking in, C. Vertical on looking down, D. Horizontal on looking out
C: Vertical on looking down
Answer: C: Vertical on looking down 
Explanation: Diplopia—seeing double—is a symptom with many potential causes, both neurological and .
This group of patients may also describe palinopsia—multiple images .
However, other causes of an apparent superior oblique palsy such as .
The optokinetic system cannot be properly assessed at bedside because the OKN