text: which of the following is not true of rna processing? a. exons are excised and hydrolyzed before mrna moves out of the nucleus. b. the presence of introns may facilitate crossing over between regions of a gene that code for polypeptide domains. c. ribozymes may function in rna splicing. d. rna splicing may be catalyzed by sliceosomes. e. a primary transcript is often much longer than the final rna molecule that leaves the nucleus.  studying for a bio exam, having trouble finding the answer. thank you =] hi the answer may be a or e. most probably a.