Which of the Following Describes the Effect of the Transformation $g(x)=9 f\left(\frac{x}{9}\right)$

Multiple Choice

Which of the following describes the effect of the transformation $g(x) =9 f\left(\frac{x}{9}\right)$ on the graph of the function $f$ ?

A) The graph is stretched vertically by a factor of 9 and stretched horizontally by a factor of 9.
B) The graph is stretched vertically by a factor of 9 and shrunk horizontally by a factor of $\frac{1}{9}$ .
C) The graph is shrunk vertically by a factor of $\frac{1}{9}$ and stretched horizontally by a factor of 9 .
D) The graph is shrunk vertically by a factor of $\frac{1}{9}$ and shrunk horizontally by a factor of $\frac{1}{9}$ .