Compute the Exact Value of the Function for the Given $f ( x ) = \left( \frac { 1 } { 4 } \right) ^ { x }$

Multiple Choice

Compute the exact value of the function for the given x-value without using a calculator.
- $f ( x ) = \left( \frac { 1 } { 4 } \right) ^ { x }$ for $x = - 3$

A) $\frac { 1 } { 64 }$
B) 64
C) $- 12$
D) $- \frac { 1 } { 64 }$