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
A wave in ERG is due to activity of: 
Select and explain. 
A. Pigmented epithelium, B. Rods and cones, C. Ganglion cell, D. Bipolar cell
B: Rods and cones
Answer: B: Rods and cones 
Explanation: Ans. Rods and cones