If $m ( x ) = x ^ { 3 }$

Multiple Choice

If $m ( x ) = x ^ { 3 }$ and $n ( x ) = \sqrt { 6 + x }$ find the function value, if possible.
$\left( \frac { m } { n } \right) ( - 6 )$

A) $- \frac { 108 } { \sqrt { 3 } }$
B) $- 216$
C) 0
D) Undefined