Solve the Equation $$4 ^ { - x } = \frac { 1 } { 16 }$$

Multiple Choice

Solve the equation.
- $$4 ^ { - x } = \frac { 1 } { 16 }$$

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