The function g(x) = x2 is transformed to obtain function h: h(x) = g(x − 3).
Which statement describes how the graph of h is different from the graph of g?

A. The graph of h is the graph of g horizontally shifted right 3 units.
B. The graph of h is the graph of g horizontally shifted left 3 units.
C. The graph of h is the graph of g vertically shifted up 3 units.
D. The graph of h is the graph of g vertically shifted down 3 units.