Rationalize the Denominator and Simplify $\sqrt { \frac { 1 } { 2 } }$

Multiple Choice

Rationalize the denominator and simplify. Assume that all variables represent positive real numbers.
- $\sqrt { \frac { 1 } { 2 } }$

A) $\frac { \sqrt { 2 } } { 4 }$
B) 1
C) $\sqrt { 2 }$
D) $\frac { \sqrt { 2 } } { 2 }$