The correct option is C Chromatophores
Chromatophores are the pigment containing membranous structures that serve as the site for photosynthesis in BGA. They are the bubbles of liquid, that form on the membranes of bacteria that absorb sunlight, carbon dioxide and water to produce the energy needed for respiration and other functions. These bacteria use chromatophores to store the proteins necessary for photosynthesis. Thus, the correct answer is option C.