Factor Completely $y^{2}-49$ A) $(y-7)(y-7)$ B) $(y+49)(y-49)$ C) $(\mathrm{y}+7)(\mathrm{y}-7)$ D) $\left(y^{2}+7\right)\left(y^{2}-7\right)$

Factor completely.
- $y^{2}-49$

A) $(y-7) (y-7)$
B) $(y+49) (y-49)$
C) $(\mathrm{y}+7) (\mathrm{y}-7)$
D) $\left(y^{2}+7\right) \left(y^{2}-7\right)$