Answer:
The correct answer is to unwind the duplex DNA.
Step-by-step explanation:
DNA helicase is the first essential enzymes during replication which unwinds the double stranded DNA at the origin of replication.
DNA helicase works in a manner as follows:
1. Helicase binds to the origin of replication where synthesis will start.
2. Enzyme starts unwinding the double-stranded DNA by melting the hydrogen bonds between them using energy in the form of ATP.
3. Enzyme continues the process of unwinding the DNA by forming a structure called the replication fork.
Thus, the correct answer is to unwind the duplex DNA.