Use a graphing utility and the change-of-base formula to determine the graph of the function. y = log 4(x - 1) a The graph of a logarithmic function shifted down 1 unit. The graph increases left to right. b The graph of a logarithmic function shifted right 1 unit. The graph increases left to right. c The graph of an exponential curve increasing left to right shifted right 1 unit. d The graph of an exponential curve increasing left to right shifted down 1 unit