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
Arden index is related to – 
Select and explain. 
A. ERG (Electroretinogram), B. EOG (Electroculogram), C. VER (Visual Evoked response), D. Perimetry
B: EOG (Electroculogram)
Answer: B: EOG (Electroculogram) 
Explanation: Arden index is related to Electrooculography
Interpretation of results:- Results of EOG are interpreted by finding out the Arden ratio as follows :

Arden ratio = Minimum height of light peak / Minimum height of dark trough  x 100

Normal curve values are 185 or above.
Subnormal curve values are less than 150.
Flat curve values are less than 125.