Q: In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
Question: Which of the following modifications is not part of the maturation process suffered by the precursors of the tRNAs?
Options: <1> Modification of bases. <2> Elimination of the 5'-end leader sequence. <3> Elimination of the final segment of the 3 'end. <4> Addition of CCA to the 3 'end. <5> Polyadenylation of the 3'-end.
A:
5