How many unique possible combinations of nucleotide bases are there to make the amino acids needed for protein synthesis? 24

64

60

20

I think this is 20 Brainliest?

Explanation:

Each group of three nucleotides encodes one amino acid. Since there are 64 combinations of 4 nucleotides taken three at a time and only 20 amino acids, the code is degenerate (more than one codon per amino acid, in most cases). The adaptor molecule for translation is tRNA

trachea, alveoli, lung capillaries, arteries