Give the Equation of the Function G Whose Graph Is $f ( x ) = \left| x ^ { 2 } + 6 x \right|$

Give the equation of the function g whose graph is described.
-The graph of $f ( x ) = \left| x ^ { 2 } + 6 x \right|$ is horizontally stretched by a factor of 3 .

A) $g ( x ) = 3 \left| x ^ { 2 } + 6 x \right|$
B) $g ( x ) = \left| \frac { 1 } { 3 } x ^ { 2 } + 2 x \right|$
C) $g ( x ) = \left| 9 x ^ { 2 } + 18 x \right|$
D) $g ( x ) = \left| \frac { 1 } { 9 } x ^ { 2 } + 2 x \right|$