Write the Polynomial $x ^ { 4 } - 6 x ^ { 2 } - 72$

Multiple Choice

Write the polynomial $x ^ { 4 } - 6 x ^ { 2 } - 72$ as the product of linear and quadratic factors that are irreducible over the reals.

A) $( x + 2 \sqrt { 3 } ) ( x + 2 \sqrt { 3 } ) \left( x ^ { 2 } + 6 \right)$
B) $( x - 2 \sqrt { 3 } ) ( x - 2 \sqrt { 3 } ) \left( x ^ { 2 } + 6 \right)$
C) $( x + 2 \sqrt { 3 } ) ( x - 2 \sqrt { 3 } ) \left( x ^ { 2 } - 6 \right)$
D) $( x + 2 \sqrt { 3 } ) ( x - 2 \sqrt { 3 } ) \left( x ^ { 2 } + 6 \right)$
E) $( x + 2 \sqrt { 3 } ) ( x + 2 \sqrt { 3 } ) \left( x ^ { 2 } - 6 \right)$