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: Biochemistry
Which of the following is a component of the visual pigment rhodopsin 
Select and explain. 
A. β-carotene, B. Retinal, C. Retinol, D. Retinoic acid
B: Retinal
Answer: B: Retinal 
Explanation: In the retina, retinal (retinaldehyde) functions as the prosthetic group of light-sensitive opsin proteins, forming rhodopsin (in rods) and iodopsin (in cones).