Final answer:
Ribosomal RNA in bacteria is an example of gene redundancy found in both eukaryotes and prokaryotes, reflecting a common mechanism of protein synthesis and evidence for a shared ancestry.
Step-by-step explanation:
An example of gene redundancy that occurs in both eukaryotes and prokaryotes is B) Ribosomal RNA in bacteria. This redundancy can also be observed in eukaryotic organisms such as humans, where ribosomal RNA plays a critical part in the structure and function of ribosomes, which are essential for protein synthesis. In both types of cells, multiple copies of rRNA genes ensure the production of a large number of ribosomes necessary to meet the demands of the cell for protein synthesis.
Additional features that provide evidence for common ancestry include the universal genetic code, similar mechanisms of gene regulation, and common metabolic pathways like glycolysis. These shared characteristics suggest that all living organisms evolved from a common ancestor that already possessed these fundamental biological processes.