Why must reverse transcriptase be used to create a eukaryotic expression library?
a. reverse transcriptase is only used to create a eukaryotic expression libraries
b. reverse transcriptase creates cdna from mrna in prokaryotes
c. reverse transcriptase ensures the gene is in the correct orientation within the expression vector to create protein
d. reverse transcriptase creates cdna from mrna because genes in eukaryotes have large numbers of non-coding regions
e. no other enzymes are ussed to create expression libraries except restriction enzymes.