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
Cause of cherry red spot 
Select and explain. 
A. CRVO, B. Berlin's odema, C. Eales disease, D. All of the above
B: Berlin's odema
Answer: B: Berlin's odema 
Explanation: Most important cause is trauma (Berlin's odema).