Which of the following organelles is absent in a plant cell?

Plant and animal cells share many organelles, but each type also carries a few structures characteristic of it and largely absent from the other. A plant cell is characteristically built with a rigid cellulose cell wall, plastids (such as chloroplasts), and a large central vacuole. An animal cell, by contrast, is characteristically built with a centrosome -- a microtubule-organising centre containing a pair of centrioles that organises the spindle fibres during cell division.

Applying this to each option: a cellulose cell wall is present, forming the rigid outer boundary of the plant cell. Vacuoles are present -- a plant cell typically has one large central vacuole for turgor pressure and storage. Plastids are present -- chloroplasts, chromoplasts and leucoplasts are characteristic plant organelles for photosynthesis and storage. A centrosome, being the animal-cell structure described above, is not part of a plant cell's standard organelle set -- plant cells assemble their spindle apparatus without centrioles.

As a cross-check: an animal cell has a centrosome but lacks a cell wall, plastids, and a large central vacuole -- the reverse pattern -- which confirms these two lists of characteristic structures are complementary. (This holds for the higher plants -- angiosperms and most gymnosperms -- that competitive exams test on; a few gymnosperms such as cycads and Ginkgo, along with lower plants and algae with motile, flagellated sperm cells, are textbook exceptions that do form centrioles, outside the usual exam scope.)