Final answer:
Thylakoids, DNA, and ribosomes are components which can be found in chloroplasts, where thylakoids contribute to photosynthesis, chloroplast DNA carries essential genes, and chloroplast ribosomes aid in synthesizing proteins.
Step-by-step explanation:
Thylakoids, DNA, and ribosomes are all components found in chloroplasts (Option B). Thylakoids are membrane-bound compartments inside chloroplasts and are the sites where photosynthesis occurs. They often exist as stacks called grana. DNA in chloroplasts is quite significant as like mitochondria, chloroplasts have their own DNA, which is separate from the nuclear DNA. This circular DNA carries genes that are essential for the chloroplast's function. Lastly, chloroplasts contain their own ribosomes, which are more similar in size and characteristics to prokaryotic ribosomes than eukaryotic cytoplasmic ribosomes, and they play a critical role in protein synthesis within the chloroplast.