Add the Proper Constant to Each Binomial So That the Resulting

Multiple Choice

Add the proper constant to each binomial so that the resulting trinomial is a perfect square trinomial. Then factor the
trinomial.
- $x ^ { 2 } - 4 x +$ ______

A) $x ^ { 2 } - 4 x + ( - 16 ) = ( x - 4 ) ^ { 2 }$
B) $x ^ { 2 } - 4 x + \underline { 4 } = ( x - 2 ) ^ { 2 }$
C) $x ^ { 2 } - 4 x + ( - 4 ) = ( x - 2 ) ^ { 2 }$
D) $x ^ { 2 } - 4 x + \underline { 16 } = ( x - 4 ) ^ { 2 }$