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
Which tissue consumes the highest oxygen? 
Select and explain. 
A. Choroid, B. Lens, C. Retina, D. Ciliary epithelium
C: Retina
Answer: C: Retina 
Explanation: Retina is the highest oxygen consuming tissue of not only the eye but also amongst one of the most richly perfused tissues of body.