Find the Length of a Radius of Each Circle $r = 20$

Multiple Choice

Find the length of a radius of each circle. Match each of the equations with length of a radius to obtain a true statement.
- $r = 20$

A) $x ^ { 2 } + y ^ { 2 } = 3$
B) $x ^ { 2 } + y ^ { 2 } + 14 x + 6 y + 39 = 0$
C) $x ^ { 2 } + y ^ { 2 } - 12 x + 20 y + 101 = 0$
D) $x ^ { 2 } + y ^ { 2 } + 24 x - 32 y = 0$