The correct option is B Photosynthesis
Chromatophore - A plastid, colored because of the presence of chlorophyll or other pigments, found in certain forms of protozoa. They are involved in the process of photosynthesis.
Chromatophores are pigment containing and light reflecting cells, or group of cells, found in bacteria and a wide range of animals including amphibians, fishes, reptiles etc.
These are found in membranes of phototrophic bacteria. used primarily for photosynthesis, they contain bacteriochlorophyll pigments and carotenoids.
So, the correct answer is option B.