This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anatomy, Subject name: Ophthalmology
[{'content': 'What is the depth of the anterior chamber? \nSelect and explain. \nA. 2.5 to 3.5mm, B. 3.5mmto4.5mm, C. 4.5mm to 5.5mm, D. 5.5 mm to 6.5mm', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., 2.5 to 3.5mm o 'The normal depth of anterior chamber of eye is 3.5mm to 2.5mm; less than 2.5mm depth can be risk for angle closure glaucoma.'", 'role': 'assistant'}]