Factor Completely $x^{4}-1$ A) $(x+1)^{2}(x-1)^{2}$ B) $\left(x^{2}-1\right)(x-1)(x+1)$ C) $\left(x^{2}+1\right)(x-1)(x+1)$ D) $\left(x^{2}+1\right)\left(x^{2}-1\right)$

Multiple Choice

Factor completely. If the polynomial cannot be factored, write "prime."
- $x^{4}-1$

A) $(x+1) ^{2}(x-1) ^{2}$
B) $\left(x^{2}-1\right) (x-1) (x+1)$
C) $\left(x^{2}+1\right) (x-1) (x+1)$
D) $\left(x^{2}+1\right) \left(x^{2}-1\right)$