The correct option is A Ribosome
Golgi apparatus has the main function of modifying, sorting and packaging the proteins, which are synthesized by cells. Golgi bodies are also involved in the transport of lipid molecules across the cell. Golgi bodies also create lysosomes.
Mitochondria produce the energy currency, i.e., ATPs of the cell. Mitochondria take nutrients and convert them into energy molecules. This process is known as 'oxidative phosphorylation'.
Plastids are present in plant cells that synthesize and store important chemical compounds used by the cell. There are many types of plastids as chloroplast, chromoplast, and leucoplasts. Chloroplast carries out photosynthesis and produce food.
Ribosomes are cell organelles, which are present in free or in bound form. They are involved in protein synthesis.