Answer
There are two specific activities: 1) The addition of the amino acid to the right tRNA, for which there is a specific enzyme for each of the 61 codons which are assigned amino acids. 2) The tRNA anticodon only base pairs with the correct codon in the mRNA being translated.
Work Step by Step
This is like saying that you get the correct groceries because quality control in the factory makes sure to put hot dogs in hot dog packages and you yourself make sure to read the package and grab the correct one in the store.
