Rate of change is expressed as a ratio between a change in one variable relative to a corresponding change in another; graphically, the rate of change is represented by the slope of a line.
The general equation of a line is given as
[tex]\begin{gathered} y=mx+c \\ \text{where m=slope} \\ c=\text{intercept on the y AXIS} \end{gathered}[/tex]Since the rate of change is represented as the slope of a line we can therefore say that the variable that represents the rate of change is the letter M
HENCE THE ANSWER IS OPTION D=M
