Decide What Values of the Variable Cannot Possibly Be Solutions $90 x ^ { - 2 } - 5 x ^ { - 1 } = 20$

Multiple Choice

Decide what values of the variable cannot possibly be solutions for the equation.
- $90 x ^ { - 2 } - 5 x ^ { - 1 } = 20$

A) $\left\{ 2 , - \frac { 9 } { 4 } \right\}$
B) $\left\{ \frac { 1 } { 2 } , - \frac { 4 } { 9 } \right\}$
C) $\left\{ \frac { 1 } { 2 } , \frac { 4 } { 9 } \right\}$
D) $\left\{ - \frac { 1 } { 2 } , - \frac { 4 } { 9 } \right\}$