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
[{'content': 'Most common type of staphyloma in myopia is: \nSelect and explain. \nA. Posterior, B. Intercalary, C. Equatorial, D. Ciliary', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Posterior', 'role': 'assistant'}]