Review the function of each pigment option provided: Chlorophyll a is a photosynthetic pigment found in plants, algae, and cyanobacteria, and is unrelated to vision. Carotene is a pigment involved in photosynthesis and also serves as a precursor to vitamin A, which is important for vision but not directly responsible for night vision. Phycoerythrin is a pigment found in red algae and cyanobacteria, used for capturing light energy in photosynthesis.