Which of the following processes only occurs in eukaryotic mRNA transcript modification and gene expression?
A. mRNA, tRNA, and rRNA are transcribed.
B. Transcription can begin as soon as translation has assembled the first few amino acids in the polypeptide.
C. A poly-A tail is added to the 3' end of an mRNA, and a cap is added to the 5' end.
D. RNA polymerase binds to the promoter.