Answer:
The correct answer would be - Two major types of mutations are deletions and substitutions.
Step-by-step explanation:
The two major types of mutations are deletion and substitution, other than these there are many more mutations that are categorized under gene mutations and chromosomal mutation.
The deletion mutation takes place in the conditions where the DNA deletes or missed copying the nucleotide in a new DNA molecule. This type of mutation can occur in one or more nucleotides. Whereas Substitution mutation occurs when there is a wrong nucleotide added to the DNA sequence or substitute with other.
Both could be deleterious and takes place at the nucleotide level. Both mutation depends on the number of nucleotide or the location of the mutation on the gene.