In Reference to DNA Mutations,which of the Following Is a Mismatched

In reference to DNA mutations,which of the following is a mismatched pair?

A) Base insertion: frameshift
B) Pyrimidine switched for a purine: transition
C) Reversal of primary mutation to functional phenotype: suppressor mutation
D) Premature stop codon: non-functional protein
E) Point mutation with no change in amino acid: silent mutation