Rate of Change is the same as Slope.
A.

Convert to slope-intercept form.
Subtract 14x to both sides:

Divide -2 to both sides:

So the rate of change here is 7.
B.

This is already in slope-intercept form, so the rate of change here is 6.
C.
Take any two points on the graph and plug them into the slope formula.
Let's take (-1, -2) and (0, 3).
x1 y1 x2 y2

Plug in the numbers:

Subtract:

Divide:

So the rate of change here is 5.
D.
Take any two points on the line and plug them into the slope formula.
Let's take (0, -2) and (1, 3)
x1 y1 x2 y2

Plug in the numbers:

Subtract:

Divide:

So the rate of change here is 5.
Therefore, A has the greatest rate of change.