Which of these best describes the role of helicase and DNA polymerase in DNA replication? *
A. DNA polymerase "unzips" the DNA strand, while helicase brings in new strands of DNA to match the old strands
B. Helicase attaches new nitrogen bases to the ends of old DNA strands, while DNA polymerase breaks down unused DNA strands
C . DNA polymerase breaks down the old strand of DNA after a new one has been replicated, while helicase connects the two DNA strands together
D. Helicase "unzips" the DNA strand, while DNA polymerase brings in new strands of DNA to match the old strands
