In this problem, we're looking at the number of fruit flies, \( f(t) = 8(2)^t \), after \( t \) days. Since Annabel bakes the banana bread 5 days after returning from the market, the appropriate domain for \( t \) is from 0 to 5 days.
Thus, the correct response indicating the appropriate domain for the problem is:
0 ≤ t ≤ 5.