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
A child presents with unilateral propotosis which is compressible and increases on bending forwards. It is non-pulsatile and has no thrill or bruit. MRI shows retroorbital mass with ecogenic shadows (with enhancement). The most probable diagnosis is: 
Select and explain. 
A. Neurofibromatosis, B. Orbital varix, C. Orbital A-V fstula, D. Orbital encephalocele
B: Orbital varix
Answer: B: Orbital varix 
Explanation: B i.e. Orbital varix