Given the task definition and input, reply with output. In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.

Question: What RNA eukaryotic polymerase is involved in the transcription of messenger RNA (mRNA) ?:
Options: <1> RNA Polymerase I. <2> RNA Polymerase II. <3> RNA Polymerase III. <4> RNA Polymerase IV. <5> Transcription of mRNA is carried out jointly by RNA Polymerase I and RNA Polymerase II.
2