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
Basic lesion in tobacco amblyopia is: 
Select and explain. 
A. Degeneration of ganglion cells especially of macular region, B. Degeneration of foveal cones, C. Ischaemia of optic nerve fibres, D. All of the above
A: Degeneration of ganglion cells especially of macular region
Answer: A: Degeneration of ganglion cells especially of macular region 
Explanation: Ans. Degeneration of ganglion cells especially of macular region