Answer:
During Transcription, an mRNA is created in the nucleus.
Explanation:
Transcription is the mechanism where the genetic information contained in one strand of the DNA molecule is decoded in the messenger RNA (mRNA) molecule, which will be subsequently used as template to synthesize a protein during translation. In eukaryotes, transcription is a nuclear process that has three phases: initiation, elongation and termination. During initiation, an RNA polymerase enzyme and different transcription factors form the initiation complex that binds to the promoter gene region and thus synthesizes the first RNA nucleotides. Subsequently, this RNA sequence is elongated by the action of the RNA polymerase. Finally, during termination, the terminator sequence in the DNA template induces the release of the DNA and this mRNA sequence is terminated.