Factor Completely $$x ^ { 2 } + 4 x - 21$$

Multiple Choice

Factor completely. If the polynomial cannot be factored, write ʺprime.ʺ
- $$x ^ { 2 } + 4 x - 21$$

A) $( x - 21 ) ( x + 4 )$
B) $( x - 7 ) ( x + 3 )$
C) $( x + 7 ) ( x - 3 )$
D) Prime