A slope indicates how much the value of vertical scale(y) is changing in comparison to the value on horizontal scale(x).
Change in y divided by Change in x shows the rate of change. So the slope shows the rate of change of a variable. The greater the value of the slope, the greater will be the rate of change. For a smaller value of slope, the rate of change will be the smaller.
From the given options, the largest value of the slope is 14.225. So option A indicates the greatest rate of change