Final answer:
The final step in DNA replication where mRNA is decoded by a ribosome to produce an amino acid chain is translation, resulting in the formation of a complete protein.
Step-by-step explanation:
The final step in DNA replication involves the decoding of mRNA by a ribosome to produce an amino acid chain which will fold into a protein. This process is known as translation. During translation, tRNA molecules carry amino acids to the ribosome, where their anticodons match with the codons on the mRNA strand. Each match adds an amino acid to the elongating polypeptide chain. This polypeptide formation continues until a stop codon is reached, signaling the end of the translation process and resulting in a complete protein that can then fold into its functional form.