Add
- $\left(3 x^{2}-2 x y+y^{2}\right)+\left(3 x^{2}+4 x y-y^{2}\right)+\left(x^{2}+x y-y^{2}\right)$ A) $7 x^{2}+3 x y+y^{2}$

Multiple Choice

Add.
- $\left(3 x^{2}-2 x y+y^{2}\right) +\left(3 x^{2}+4 x y-y^{2}\right) +\left(x^{2}+x y-y^{2}\right)$

A) $7 x^{2}+3 x y+y^{2}$
B) $5 x^{2}+1 x y-y^{2}$
C) $6 x^{2}+2 x y-y^{2}$
D) $7 x^{2}+3 x y-y^{2}$