Simplify the Expression $\left( \frac { 5 } { x } \right) ^ { 2 }$

Multiple Choice

Simplify the expression. Assume all variables represent nonzero real numbers.
- $\left( \frac { 5 } { x } \right) ^ { 2 }$

A) $\frac { 5 } { x ^ { 2 } }$
B) $\frac { 25 } { x }$
C) $25 x ^ { 2 }$
D) $\frac { 25 } { x ^ { 2 } }$