This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Neuro-ophthalmology, Subject name: Ophthalmology
Congenital pit in optic nerve causes 
Select and explain. 
A. Macular retinal detachmnet, B. Visual field defects, C. Central serous retinopathy, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Optic disc pit - vision is normal in the absence of complications. The disc is often larger than normal and contains a greyish round or oval pit of variable size , usually temporal but occasionally central. Visual field defects are common and may mimic glaucoma. Serous macular detachment develops in about half of eyes with non-central disc pits. Ref: kanski's 8th edition, page no.798