Decide What Values of the Variable Cannot Possibly Be Solutions $$\sqrt [ 4 ] { x + 9 } = \sqrt [ 4 ] { 5 x }$$

Multiple Choice

Decide what values of the variable cannot possibly be solutions for the equation.
- $$\sqrt [ 4 ] { x + 9 } = \sqrt [ 4 ] { 5 x }$$

A) $\left\{ \frac { 4 } { 9 } \right\}$
B) $\left\{ \frac { 9 } { 4 } \right\}$
C) $\varnothing$
D) $\left\{ \frac { 9 } { 5 } \right\}$