Let's evaluate the two statements:
Statement I: "Transfer RNAs and ribosomal RNA do not interact with mRNA" is incorrect. Both transfer RNA (tRNA) and ribosomal RNA (rRNA) play crucial roles in protein synthesis by interacting with mRNA. tRNA carries amino acids to the ribosome, where rRNA facilitates protein synthesis by catalyzing the formation of peptide bonds between amino acids.
Statement II: "RNA interference (RNAi) takes place in all eukaryotic organisms as a method of cellular defence" is correct. RNA interference is a biological process that occurs in many eukaryotic organisms and involves small RNA molecules that regulate gene expression by degrading mRNA or inhibiting translation. It serves as an important defense mechanism against viruses and transposons.
Thus, the correct answer is Statement I is incorrect but Statement II is correct.