An elongating ribosome is bound to appropriate trnas in both the a and p sites and is ready for peptidyl transfer. what happens next?

(a) the carboxyl end of the polypeptide chain is released from the p-site trna and joined to the free amino group of the amino acid linked to the a-site trna.
(b) the carboxyl end of the amino acid is released from the a-site trna and joined to the free amino group of the polypeptide chain linked to the p-site trna.
(c) the trna with the growing peptide chain is translocated to the e-site where the amino acid from the a-site trna will be linked to the polypeptide chian.
(d) the trna with the amino acid attached is translocated to the e-site before it is linked to the growing polypeptide chain.