The correct options are
A Addition of 3 or multiples of 3 base paits
C Deletion of 3 base pairs
A non-frameshift mutation can happen only when there is an addition or deletion of 3 or multiples of 3 base pairs. This kind of mutation does not disturb the overall composition of the polypeptide, but can still damage the protein stucture, as an amino acid may be absent or additionally present respectively.