Answer: Elongation
Step-by-step explanation:
Elongation (in the context of DNA) is not a form of post translational modification. It is basically an increase in the length of a particular growing nucleotide chain during either replication, translation or transcription. Post translation modifications are basically changes that are most of the times chemical that can take place in a protein after translation and some of these occur to activate or to cleave some specific regions. Examples including phosphorylation, glycosylation (conjugation of carbohydrate by enzymes) etc