One type of gene mutation involves a base substitution.

What are the consequences of the base substitutions in the two new sequences of DNA?

A. Both are mutations that would result in different polypeptides.
B. Sequence 2 would result in a changed polypeptide but sequence 1 would not.
C. All three DNA sequences would translate into the same polypeptide.
D. Only the original DNA and sequence 2 would translate into the same polypeptide.

D

This question caused concern from three teachers due to the ambiguity of the term "different" polypeptides, as in different with respect to one another or different with respect to the original DNA sequence. In such cases of ambiguous interpretation, students should be advised to read all possible answers. Choice D could then be recognized as unequivocally correct.