Minumum no. of bases needed to code for enzyme

Ok, I'm doing a AQA biology past paper. This question crops up:

Ribonuclease is an enzyme. It is 127 amino acids long.
What is the minimum number of DNA bases needed to code for ribonuclease?

The answers accepted are: 381, 384 and 387

I know the answers...but why is it 3 x the no of amino acids in the original enzyme? I thought 2 x ...... please, please, please explain your answer in a A Level standard, so not university level stuff but not primary school level either.

Easy 10 points, I'll choose answer in next 24 hours dependant on quality of answers

DNA-->RNA--> Protein , every three bases (triplet) code for one aminoacid, sometimes they can code to stop the translation, and it's possible for some sequences to code for the same aminoacid.

So basically behind each aminoacid made there are 3 bases that coded for it, that's why it's 3 times the number of aminoacids.

i hope that helped.

It is 3 times the number of amino acids because a codon codes for one amino acid and one codon is three nucleotide bases long!