Find the Center and Radius of the Circle with the Given

Multiple Choice

Find the center and radius of the circle with the given equation.
- $$x ^ { 2 } + y ^ { 2 } = 9$$

A) Center $( 3,3 ) , r = 3$
B) Center $( 0,0 ) , r = 3$
C) Center $( 3,3 ) , r = 9$
D) Center $( 0,0 ) , r = 9$