Factor as Completely as Possible $$x ^ { 2 } - 6 x + 36$$

Multiple Choice

Factor as completely as possible. If unfactorable, indicate that the polynomial is prime.
- $$x ^ { 2 } - 6 x + 36$$

A) $( x - 6 ) ^ { 2 }$
B) Prime
C) $( x + 6 ) ( x - 6 )$
D) $( x + 6 ) ^ { 2 }$