The study of genes is called genetics. There are two types of genes and these genes are recessive and dominant.
The correct answer to the question is 12.
Each amino acid is coded by the 3 codons, therefore to form 4 amino acids the codon required from the chain will be
4*3=12
Hence, the 12 codons are required.
For more information about codon, refer to the link:-
https://brainly.com/question/787658