<u>Answer</u>: Option D. RNA polymerase.
<u>Explanation</u>:
- Transcription is the process which is used to produce RNA from a DNA template.
- The enzyme involved in the process of transcription is <em>RNA</em> <em>polymerase</em> which is responsible for separating the DNA strands and making an RNA which is complementary to the DNA.
- RNA polymerase joins the nucleotides in the newly formed RNA strands by utilizing the energy released from the cleavage of the additional phosphate bonds that are removed by it.
- The RNA polymerase dissociates from the DNA only after the process of transcription is complete.
Attached is an image with the correct labeling.
