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 etiology of posterior staphyloma is ? 
Select and explain. 
A. Trauma, B. Glaucoma, C. Degenerative axial myopia, D. Scleritis
C: Degenerative axial myopia
Answer: C: Degenerative axial myopia 
Explanation: Ans. is 'c' i.e., Degenerative axial myopia