Answer :
The forms of RNA not present naturally in both eukaryotes and prokaryotes are: (a) CRISPR RNA.
RNA stand for Ribonucleic acid. It is transcribed form of DNA made by using the enzyme RNA polymerase. There are broadly two categories of RNA: coding and non-coding. m-RNA belongs to the category of coding RNA whereas t-RNA and r-RNA are the non-coding ones.
Crispr RNA is the adaptation of a type of RNA that is found in the bacterial cells that they use for there defense and immunity. In this the Crispr RNA acts as a spacer sequence that makes small guide RNAs that guide the host RNA to kill the foreign particles.
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