Find the Least Common Denominator of the Rational Expressions $\frac { 4 } { x ^ { 2 } - 36 }$

Multiple Choice

Find the least common denominator of the rational expressions.
- $\frac { 4 } { x ^ { 2 } - 36 }$ and $\frac { 8 } { x - 6 }$

A) $( x + 6 ) ( x - 6 )$
B) $\left( x ^ { 2 } + 6 \right) \left( x ^ { 2 } - 6 \right)$
C) $x ( x - 6 )$
D) $( x + 6 ) ( x - 6 ) ^ { 2 }$