Answer:
C: Before Aisha could say something that she'd regret, she bit her mouth.
Step-by-step explanation:
This sentence uses the idiom bite your tongue because Aisha wants not only to avoid speaking, but also saying something she would regret. The idiom bite your tongue means to try hard to stop yourself from saying what you really think.
A. Chew somebody out: rebuke
B: Shut your mouth: to stop talking
C. Crack somebody up: laugh