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': 'Facility of aqueous outflow is ______I/min/mm Hg. – \nSelect and explain. \nA. 0.8, B. 0.6, C. 0.4, D. 0.2', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The average C-value (facility of aqueous outflow) is 0.28 ± 0.05 1/min/mmHg.', 'role': 'assistant'}]