This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diseases of the Optic Nerve, Subject name: Ophthalmology
Pupillary reaction to light is still normal in lesion/injury to 
Select and explain. 
A. Optic nerve, B. Optic disc, C. Optic tract, D. Optic chiasm
B: Optic disc
Answer: B: Optic disc 
Explanation: Ans. (b) Optic disc* Optic disc is not involved in papillary light reflex.* Pathway of papillary light reflex:Retina - Optic Nerve - Optic Chiasma - Optic Tract - Prerectal Nucleus - Edinger Westphal Nucleus - Inferior Division of 3rd Nerve - Ciliary Ganglion - Short Ciliary Nerves - Sphincter Pupillae