Explanation:

Both the statements are correct.

MicroRNAs

• MiRNAs are small, evolutionary conserved, single-stranded, non-coding RNA molecules that bind target mRNA to prevent protein production by one of two distinct mechanisms.

• Mature miRNA is generated through two-step cleavage of primary miRNA (pri-miRNA), which is incorporated into the effector complex RNA-induced silencing complex (RISC).

• The miRNA functions as a guide by base-pairing with the target mRNA to negatively regulate its expression.

• The level of complementarity between the guide and mRNA target determines which silencing mechanism will be employed; cleavage of target messenger RNA (mRNA) with subsequent degradation or translation inhibition.

mRNA 

• Messenger RNA (mRNA) is a type of single-stranded RNA involved in protein synthesis.

• mRNA is made from a DNA template during the process of transcription.

• The role of mRNA is to carry protein information from the DNA in a cell’s nucleus to the cell’s cytoplasm (watery interior), where the protein-making machinery reads the mRNA sequence and translates each three-base codon into its corresponding amino acid in a growing protein chain.

• So mRNA really is a form of nucleic acid that helps the human genome, which is coded in DNA, to be read by the cellular machinery.

Hence option 3rd is correct.