Evaluate If Possible $\left( 27 ^ { - 1 / 3 } \right) ^ { 0 }$

Multiple Choice

Evaluate if possible. If the expression is not a real number, so state.
- $\left( 27 ^ { - 1 / 3 } \right) ^ { 0 }$

A) $\frac { 1 } { 3 }$
B) 3
C) 1
D) not a real number