Take another look at the sentence:
Using bites of bologna as bribes, Diane convinced Reliable, her beagle, to lie still, and then she __________ each of his eighteen toenails.
The sentence requires the simple past of cut, an irregular verb that never changes form. Cut is the simple past.
|Verb||Simple Present||Simple Past||Past Participle|
Cuted, the form you chose, is a spelling error. Before you continue, review the rules for irregular verbs.