Answer:
The correct answer will be option-A.
Explanation:
RNA polymerase is the enzymes which perform the process of transcription that synthesizes the RNA from one strand of the DNA.
These polymerase moves step-wise along the DNA strand adding one nucleotide in  5′-to-3′ direction. They catalyze the reaction by forming the phosphodiester bond between two nucleotides using the energy from the high energy bonds of ATP and form the linear RNA.
Thus, option-A is the correct answer.
