Which polymerase is responsible for the initiation of DNA replication and has primase activity in eukaryotes?

DNA Polymerase α is the correct answer because it possesses primase activity, which is essential for initiating DNA replication in eukaryotic cells. During DNA replication, this polymerase synthesizes a short RNA primer that provides a starting point for DNA synthesis.

In the eukaryotic replication process, DNA Polymerase α works alongside the primase enzyme to create these short RNA primers. The importance of this priming activity is that no DNA polymerase can initiate the synthesis of a new DNA strand without an existing strand to extend; thus, primase activity is crucial for providing this essential precursor.

Following the synthesis of the RNA primer, DNA Polymerase α continues to add deoxynucleotides to initiate the elongation phase of DNA replication before being replaced by other polymerases that carry out the bulk of DNA synthesis, such as DNA Polymerase δ and ε.

Understanding the role of DNA Polymerase α in the initiation of replication, rather than its subsequent roles in elongation or repair, highlights its unique function in eukaryotic DNA replication and underscores why it is the right choice among the options provided.