This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Special Senses: Vision and its Elements, Subject name: Physiology
[{'content': 'During the dark phase of visual cycle, which form of vitamin A combines with opsin to make Rhodopsin: \nSelect and explain. \nA. All trans-Retinaldehyde, B. all trans-Retinol, C. 11-cis-Retinaldehyde, D. 11-cis-Retinol', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C. 11-cis-RetinaldehydeFirst know about the forms of Vitamin Aa. Retinol: A primary alcohol containing a bionone ring with an unsaturated side chain.b. Retinal: It is an aldehyde which is derived from the oxidation of alcohol. It can exist in two formsi. 11-cis retinalii. 11-trans retinalc. Retinoic acid The acid derived from oxidation of retinal(Oxidation) (Oxidation)Retinol -------- Retinal ---------- Retinoic acid(Retinaldehyde)', 'role': 'assistant'}]