Each statement describes a transformation of the graph of y = x. Which statement correctly describes the graph of y = x - 4?
A. It is the graph of y = x translated 4 units to the right.
B. It is the graph of y = x translated 4 units to the left.
C. It is the graph of y = x translated 4 units up.
D. It is the graph of y = x where the slope is decreased by 4.