RNA polymerase I is specifically devoted to transcription of three largest species of rRNAs, which are designated 28S, 18S, and 5.8S according to their rates of sedimentation during velocity centrifugation...

So, correct answer is 5Sr...

$$Hope it's help... $$

Introduction:
RNA polymerase is an enzyme responsible for transcribing DNA into RNA during the process of transcription. It plays a crucial role in gene expression and the synthesis of different types of RNA molecules. In eukaryotes, RNA polymerase I is responsible for transcribing the ribosomal RNA (rRNA) genes, which encode for the major components of ribosomes.

Transcription of rRNA genes:
The RNA polymerase I enzyme transcribes a large precursor molecule known as the primary transcript, which undergoes several processing steps to generate the mature rRNA molecules. The primary transcript of rRNA genes in eukaryotes is known as the 45S precursor RNA, which contains three different types of rRNA molecules: 18S, 5.8S, and 28S. These rRNAs are components of the ribosomes and play a crucial role in protein synthesis.

Identification of the non-transcribed rRNA:
Among the given options, the 5S rRNA (option d) is not transcribed by RNA polymerase I. The 5S rRNA is transcribed by a separate RNA polymerase III enzyme. This rRNA is smaller in size compared to the other rRNAs and is found in both prokaryotes and eukaryotes.

Conclusion:
In summary, the RNA polymerase I enzyme transcribes the 45S precursor RNA, which gives rise to the 18S, 5.8S, and 28S rRNA molecules. However, the 5S rRNA is transcribed by a different RNA polymerase III enzyme. Therefore, the correct answer to the given question is option d) 5S rRNA.