This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Special Senses, Subject name: Physiology
Which molecules combine to form rhodopsin? 
Select and explain. 
A. Bathorhodopsin and 11-cis-retinal, B. Bathorhodopsin and all-trans-retinal, C. Bathorhodopsin and scotopsin, D. Scotopsin and 11-cis-retinal
D: Scotopsin and 11-cis-retinal
Answer: D: Scotopsin and 11-cis-retinal 
Explanation: Rhodopsin is the light-sensitive chemical in rods. Scotopsin and all-trans retinal are the breakdown products of rhodopsin, which has absorbed light energy. The all-trans retinal is conveed into 11-cis retinal, which can recombine with scotopsin to form rhodopsin