The correct answer will be option D (they are complementary).
Explanation:
Complementary DNA or cDNA is an edited DNA molecule synthesized from a single-stranded RNA called mRNA. The reaction of cDNA formation from mRNA is catalyzed by an enzyme called "reverse transcriptase".
The cDNA strands formed is also known as a complementary copy of mRNA as it contains no introns or non-coding sequence in its sequence similar to mRNA. cDNA is used in recombinant DNA technology to clone eukaryotic genes in prokaryotes.
Thus, option D (they are complementary) is the correct answer.
