Which of the following cell organelles contain their own DNA? A. Plastids B.…

Whether a cell organelle carries its own DNA depends on its evolutionary origin: organelles that arose from free-living prokaryotes through endosymbiosis retained a small circular genome of their own, the nucleus houses the cell's principal chromosomal genome, while organelles that are simply membrane-bound compartments for storage or transport contain no genetic material at all.

• Plastids (A) retain their own circular DNA, a legacy of the endosymbiotic cyanobacterium-like ancestor from which they evolved.

• Mitochondria (B) likewise retain their own circular DNA, inherited from the endosymbiotic alphaproteobacterium-like ancestor from which they evolved.

• The nucleus (C) houses the cell's principal genomic DNA, organised into chromosomes.

• The vacuole (D) is a single-membrane storage sac with no DNA of its own.

So among the four listed structures, DNA is present in the plastids, mitochondria and nucleus, but absent from the vacuole — matching the combination 'A, B and C'.

• 'C and D' pairs the nucleus with the DNA-free vacuole while dropping the two organelles (plastids and mitochondria) that also carry their own DNA.

• 'B and C' correctly keeps mitochondria and the nucleus but drops plastids, which equally retain their own DNA.

• 'A, B and D' correctly keeps plastids and mitochondria but wrongly swaps in the DNA-free vacuole in place of the nucleus.