Which of the following statements explains why the insertion of a nucleotide in a dna sequence could result in a phenotypic change in an organism?

When you insert a nucleotide into a DNA sequence, this is a frame shift mutation. All of the letters after the insterted nucleotide will be shifted one place, changing the whole protien which was coded for. Whatever protien was coded for by that DNA sequence is now changed, resulting in a phenotypic change.