A Short Segment of an MRNA Molecule Is Shown Below

Multiple Choice

A short segment of an mRNA molecule is shown below. The polypeptide it codes for is also shown: 5' -AUGGUGCUGAAG : methionine -valine -leucine -lysine
Assume that a mutation in the DNA occurs so that the fourth base (counting from the 5' end) of the messenger RNA now reads A rather than G. What sequence of amino acids will the mRNA now code for? (You do not need a copy of the genetic code to answer the question.)

A) methionine -methionine -leucine -lysine
B) methionine -lysine -leucine -lysine
C) methionine -valine -leucine -lysine
D) methionine -leucine -leucine -lysine
E) methionine -valine -methionine -lysine