To solve by completing the square, what needs to be moved in this equation?
x2 = 9 - 4x

A. a = 4, b = 8, c= - 3

B. a = 4, b = - 8, c = - 3

C. a = 4, b = 8, c = 3

D. a = 4, b = - 8, c = 3