Question

what is an insertion mutation?
○ the exchange of one nucleotide for another nucleotide
○ the loss of one or more nucleotide pairs in a dna molecule
○ changing a single purine nucleotide to a pyrimidine nucleotide in a dna molecule
○ the addition of one or more nucleotide pairs to a dna molecule

Explanation:

Insertion mutation is defined as adding nucleotide pairs. The first option is substitution, the second is deletion, and the third is a type of substitution (purine - pyrimidine change). Only the fourth option correctly describes insertion mutation as the addition of nucleotide pairs to DNA.

Answer:

the addition of one or more nucleotide pairs to a DNA molecule