Q.Name the three main functional types of RNA found in a cell and state, in one line each, the specific role of each in gene expression.

In RNA viruses, RNA itself carries the hereditary information (genetic RNA). In cellular organisms, mRNA merely carries a copy of a gene's message to make protein — it is a non-genetic (working) RNA. Both statements are true.

• Sentence 1: "Genetic RNA is present in RNA viruses." — TRUE. In RNA viruses (e.g. TMV, influenza, retroviruses) RNA is the genetic material, so it is genetic RNA. …

Reading the printed term as 'CODON' (it appears to be a scanning/typesetting artefact of the original word), codons — triplet nucleotide sequences that specify amino acids — occur in messenger RNA (mRNA).

Honesty note: the stem's quoted term "NODOC" is not a standard biology term; it is the exact letter-reversal of the well-known term CODON, strongly suggesting a text-extraction/printing artefact in the source document rather than a real distinct term. Answering on that basis:

…