How does the graph of f(x) = |x| compare with the graph of g(x) = 3|x| ?

A. The graph of g is a vertical compression of the graph of f.
B. The graph of g is a vertical stretch of the graph of f.
C. The graph of g is a vertical translation 3 units up of the graph of f.
D. The graph of g is a reflection of the graph of f over the x-axis.