Consider the graph of the function $f(x)$ shown below.

Using this graph, for each of the following pairs of numbers decide which is larger. Be sure that you can explain your answer.

A. $f(6)$ $f(8)$
B. $f(6) - f(4)$ $f(4) - f(2)$
C. $\frac{f(4) - f(2)}{4 - 2}$ $\frac{f(6) - f(2)}{6 - 2}$
D. $f'(2)$ $f'(8)$