The correct option is
D Complimentary DNA
Complementary DNA or cDNA is DNA synthesized from a single stranded RNA template in a reaction catalyzed by the enzyme reverse transcriptase. cDNA is often used to clone eukaryotic genes in prokaryotes. cDNA is also produced naturally by retroviruses by using their own enzyme reverse transcriptase and then integrated into the host's genome.
So, the correct answer is 'Complimentary DNA'.