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 23-year old male presents with progressive proptosis of his right eye. The proptosis increases on bending forward and is compressible. No thrill or bruit was present. Orbital ultrasound revealed an echogenic mass with foci of echo shadows. The most likely diagnosis is 
Select and explain. 
A. Orbital AV fistula, B. Orbital encephalocoecle, C. Orbital varix, D. Neurofibromatosi
C: Orbital varix
Answer: C: Orbital varix 
Explanation: Ans. c. Orbital varix