Which statement about the genetic code is true?

• A. The code uses four nucleotides in codons
• B. Many amino acids are coded by more than one codon
• C. Each amino acid is coded by a single codon
• D. There are no stop codons in the code

Answer: (B)

Genetic code uses triplet codons, each formed from the four nucleotide bases. Because there are 64 possible triplets but only about 20 amino acids, most amino acids are encoded by more than one codon, giving redundancy in the code. This redundancy is why the statement that many amino acids are coded by more than one codon is true. It’s also why the other options don’t fit: codons are three bases long, not four; there are stop codons to terminate translation, so the idea that there are no stop codons is false; and having multiple codons per amino acid is the hallmark of the degeneracy of the genetic code.