Using the following equation, find the center and radius:
x2 − 4x + y2 + 8y = −4
A. he center is located at (−2, −4), and the radius is 4.
B. The center is located at (2, −4), and the radius is 16.
C. The center is located at (−2, −4), and the radius is 16.
D. The center is located at (2, −4), and the radius is 4