Final answer:
Both prokaryotic and eukaryotic DNA replication require the activity of primase to synthesize an RNA primer, which is crucial for DNA polymerase to start building a new DNA strand.
Step-by-step explanation:
The similarity between DNA replication in prokaryotes and eukaryotes is that both require primase activity (C). Primase is an enzyme that synthesizes a short RNA primer, which is necessary as a starting point for DNA polymerases to begin synthesis of the new DNA strand. While prokaryotic organisms typically have a single origin of replication, eukaryotic chromosomes can have multiple origins. Prokaryotes generally use fewer types of DNA polymerases compared to eukaryotes, which can use up to fourteen different DNA polymerases.