Over which interval does f(t)f(t)f, left parenthesis, t, right parenthesis have positive average rate of change? Choose 1 Choose 1 (Choice A) A [-5,-1][−5,−1]open bracket, minus, 5, comma, minus, 1, close bracket (Choice B) B [-8,-2][−8,−2]open bracket, minus, 8, comma, minus, 2, close bracket (Choice C) C [-9,-8][−9,−8]open bracket, minus, 9, comma, minus, 8, close bracket (Choice D) D [2,4][2,4]open bracket, 2, comma, 4, close bracket