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
About retinitis pigmentosa all are true, EXCEPT: 
Select and explain. 
A. Night blindness, B. Waxy disc, C. Early loss of central vision, D. Attenuation of retinal vessels is seen
C: Early loss of central vision
Answer: C: Early loss of central vision 
Explanation: In retinitis pigmentosa rods are involved first followed by cones. As the disease progresses there is loss of night vision and peripheral field of vision. Only in the later stages of the disese there is loss of central vision. Retinitis Pigmentosa is a group of hereditary retinal degenerative disorder characterized by progressive dysfunction of photoreceptors, associated with progressive cell loss and atrophy of several retinal layers. Hallmark symptoms are: night blindness, progressive loss of peripheral field of vision and coalescing ring scotomas. Characteristic fundoscopic findings are: attenuated retinal aerioles, waxy pale optic disc, mottling of retinal pigment epithelium, and peripheral retinal pigment clumping (bone spicule formation). ERG shows reduced/absent retinal function. EOG lacks usual light rise.