Why Is It That the Primary Transcript in Prokaryotes Can

Multiple Choice

Why is it that the primary transcript in prokaryotes can immediately serve as mRNA while in eukaryotes it undergoes elaborate multistep processing?

A) Primary transcripts in eukaryotes contain introns that have to be removed.
B) The sigma factor in eukaryotes is unable to enter the nucleus.
C) A 5 cap is added to the prokaryotic primary transcript allowing the ribosome to start translation immediately.
D) Prokaryotes do not have a nuclear envelope and the ribosome can start translation even before transcription ends.
E) All of these choices are correct.