If x squared plus m x plus m is a perfect-square trinomial, which equation must be true?
A
x squared plus m x plus m is equal to open paren x minus 1 close paren squaredB
x squared plus m x plus m is equal to open paren x plus 2 close paren squaredC
x squared plus m x plus m is equal to open paren x plus 4 close paren squaredD
x squared plus m x plus m is equal to open paren x plus 1 close paren squared