With Regard to RNA Polymerase Proofreading Ability,which of the Following

Multiple Choice

With regard to RNA polymerase proofreading ability,which of the following is true?

A) RNA backtracking can remove noncomplementary nucleotides.
B) RNA and DNA polymerase proofreading are essentially identical.
C) There are specialized mRNA repair pathways that remove noncomplementary nucleotides.
D) No proofreading occurs.
E) A 3' → 5' exonuclease fixes all errors in mRNA.