Select the correct answer.
Which sum or difference is modeled by the algebra tiles?
-X²
1 1
OA (x²+2x+3)-(x²-2x-1)=-2x²+2
OB. (x2+2x+3)-(-x²+2x+1)=2x²+2
OC. (x²+2x+3)+(x²+2x+1)=2x²+2
OD. (x²+2x+3)+(-x2²-2x-1)=-2x²+2