Find the Term That Should Be Added to the Expression $x^{2}+8 x$

Multiple Choice

Find the term that should be added to the expression to form a perfect square trinomial. Write the resulting perfect square trinomial in factored form.
- $x^{2}+8 x$

A) $0 ;(x+4) ^{2}$
B) $16 ;(x+4) ^{2}$
C) $64 ;(x+8) ^{2}$
D) $16 ;(x-4) ^{2}$