Thoai Thoai 19-12-2019 Mathematics contestada f(x)=x^2−x−1 Over which interval does fff have an average rate of change of zero? Choose 1 answer: (Choice A) 2≤x≤3 (Choice B) −3≤x≤−2 (Choice C) −1≤x≤2 (Choice D) −5≤x≤5