Which is the first step to occur during the process of replication?

a. synthesis of leading strand on parent dna molecule
b. addition of nucleotides to the lagging strand of the growing dna molecule
c. breaking of hydrogen bonds between complementary bases of parent dna

I think the correct answer from the choices listed above is option C. The first step to occur during the process of replication would be breaking of hydrogen bonds between complementary bases of parent DNA. First, the parent DNA unwinds by breaking the hydrogen bonds that are present in the helical structure.