How does RNA polymerase unwind the DNA double helix during transcription?

During transcription, RNA polymerase binds to a specific region of the DNA called the promoter. It then unwinds the DNA double helix by breaking the hydrogen bonds between the base pairs, allowing one of the DNA strands to serve as a template for the synthesis of RNA. This process is facilitated by the enzyme's helicase activity, which helps separate the two DNA strands and create a single-stranded template for RNA synthesis.