In the function y-1=(4x)^2+7 what effect does the number 4 have on the graph, as compared to the graph of y=x^

A. It stretches the graph horizontally by a factor of 4.
B. It stretches the graph vertically by a factor of 4.
C. It shrinks the graph vertically to 1/4 the original height.
D. It shrinks the graph horizontally to 1/4 the original width