This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Retina, Subject name: Ophthalmology
[{'content': 'Which tissue consumes the highest oxygen? \nSelect and explain. \nA. Choroid, B. Lens, C. Retina, D. Ciliary epithelium', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Retina is the highest oxygen consuming tissue of not only the eye but also amongst one of the most richly perfused tissues of body.', 'role': 'assistant'}]