Which of the following is a non-sense codon?

Correct answer: (b) UAA

Explanation

A nonsense codon (stop codon) terminates protein synthesis and codes for no amino acid; the three are UAA, UAG and UGA.

UAA is therefore the nonsense codon among the options.

AUG is the start codon (Methionine), UUU codes for Phenylalanine and UGC codes for Cysteine.