Write with Positive Exponents $5 ^ { - 1 / 4 }$

Write with positive exponents.
- $5 ^ { - 1 / 4 }$

A) $\frac { 19 } { 4 }$
B) $- 5 ^ { 1 / 4 }$
C) $- \frac { 5 } { 4 }$
D) $\frac { 1 } { 51 / 4 }$