Find All Values Of $X$ Such That $f ( x ) > 0$

Multiple Choice

Find all values of $X$ such that $f ( x ) > 0$ $f ( x ) = x ^ { 4 } - 16 x ^ { 2 }$

A) $( - \infty , 4 ) \cup ( 4 , \infty )$
B) $( - \infty , - 4 ] \cup [ 4 , \infty )$
C) $( - 4,4 )$
D) $( - \infty , 4 ) \cup ( - 4 , \infty )$
E) $( - \infty , - 4 ) \cup ( 4 , \infty )$