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
The most common site of obstruction in central retinal aery is: 
Select and explain. 
A. In front of the lamina cribrosa, B. At the lamina cribrosa, C. Behind the lamina cribrosa, D. The point where the aery enters the optic nerve
B: At the lamina cribrosa
Answer: B: At the lamina cribrosa 
Explanation: Ans. At the lamina cribrosa