Answer:
Insertion mutation
Explanation:
An extra letter is added.
First we can look at the taxonomic order:
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
The largest level would be the one closest to the top of the list because it is the least specific and therefore the most inclusive. Out of the choices given, phylum is closest to the top, so that is the answer.
The intestines, I believe.
