The correct answer is structure B, that is, chloroplasts.
The procedure of photosynthesis occurs within the cells of the plants in a composition known as chloroplasts. The chloroplasts comprise a green pigment known as chlorophyll. This pigment is accountable for captivating sunlight or light energy from the Sun, which is used to split or dissociate the molecules of water into oxygen atoms and hydrogen ions, at the time of light-depending phase of photosynthesis.