The correct option is A Chloroplast
Quantasomes are particles found in the thylakoid membrane of chloroplasts. in which photosynthesis takes place. They are composed equally of lipids and proteins, which include various photosynthetic pigments and redox carriers. They occur in 2 sizes the smaller quantasome is thought to represent the site of photosystem I, the larger to represent the site of photosystem II. Hence, option A is correct.