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
Waxy pallor of optic disc is seen in which disease? 
Select and explain. 
A. Retinitis pigmentosa, B. Retinopathy of prematurity, C. Hypeensive retinopathy, D. Diabetic retinopathy
A: Retinitis pigmentosa
Answer: A: Retinitis pigmentosa 
Explanation: Ans. is 'a' i.e., Retinitis pigmentosa