Take another look at the sentence:
While Allison gripped the roof's edge, she no longer resented the many hours that her boyfriend Chris spent in the gym. After all, his strong arms would catch her when she loosened her grip and __________ to the ground below.
The sentence requires the simple past of fall, an irregular verb. Fell is the correct form.
|Verb||Simple Present||Simple Past||Past Participle|
Falled, the form you chose, is a spelling error. Before you continue, review the rules for irregular verbs.