Answer: 3
Step-by-step explanation:
To encode a single amino acid, a triplet code (codon) is required. This codon is a combination of three nucleotides of either Adenine, uracil, guanine or cytosine and are usually present in the DNA sequence.
A good example is GGA, a codon made up of three units of guanine + guanine + Adenine, and code for the amino acid Glycine