Completely Factor the Polynomial or State That the Polynomial Is $$x ^ { 4 } + 14 x ^ { 2 } + 49$$

Multiple Choice

Completely factor the polynomial or state that the polynomial is prime.
- $$x ^ { 4 } + 14 x ^ { 2 } + 49$$

A) $\left( x ^ { 2 } + 7 \right) ^ { 2 }$
B) $\left( x ^ { 2 } - 7 \right) ^ { 2 }$
C) $( x + 7 ) ^ { 2 }$
D) $( x + 7 ) ( x - 7 )$