Factor the Following Polynomial Completely $2 a ^ { 3 } - 18 a$

Multiple Choice

Factor the following polynomial completely. $2 a ^ { 3 } - 18 a$

A) $2 a ( a - 3 ) ( a + 3 )$
B) $2 a \left( a ^ { 2 } - 9 \right)$
C) $2 a \left( a ^ { 2 } + 9 \right)$
D) $2 a ( a - 3 ) ( a - 3 )$
E) none of these