In the process of protein synthesis the amino acids bind to tRNA at:

3' end

The correct answer is Option (2) → 3' end

In protein synthesis, amino acids are attached to the 3' end of tRNA. This end has a specific sequence that provides a binding site for the amino acid. tRNAs are specific for each amino acid. The anticodon site on the tRNA, which is separate from the 3' end, is responsible for recognizing the corresponding codon on the mRNA during translation.

                                             tRNA - the adapter molecule