The one aspect which is not a salient feature of genetic code is its being

Salient features of the genetic code: the codon is a triplet; one codon codes for only one amino acid, so the code is unambiguous and specific; some amino acids are coded by more than one codon, so the code is degenerate; it is read in a contiguous fashion without punctuation; and it is nearly universal.
'Ambiguous' would mean that one codon codes for more than one amino acid, which is not the case.
Hence being ambiguous is not a salient feature of the genetic code.