The number of members, f(x), in Joe's health club increased by 25% every year over a period of x years. The function below shows the relationship between f(x) and x: f(x) = 15(1.25)x Which of the following graphs best represents the function? graph of exponential function going up from left to right through the point 0 comma 1 and approximately 6 tenths comma 6 graph of exponential function going up from left to right through the point 0 comma 15 and approximately 5 comma 45 graph of exponential function going up from left to right in quadrant 1 through the point 0, 0 and continuing toward infinity graph of exponential function going up from left to right through the point 0 comma 1 and approximately 4 comma 3