Answer:
Reverse transcriptase
DNA polymerase
DNA ligase
Explanation:
cDNA library consists of cloned cDNA (complementary DNA) inserted into a host. cDNA is produced from the mature mRNA (transcriptome form the nucleus) via reverse transcriptase (synthesize single stranded DNA from RNA). Single stranded cDNA is converted into a double stranded DNA thanks to DNA polymerase. Restriction endonucleases and DNA ligase are enzymes necessary for the cloning process ( for cloning the sequences into host-bacterial plasmids).
