3. Given the quadratic equation in $x$, $x^{2}+\left(a^{2}-1\right) x+a-2=0$, one root is greater than 1 and the other root is less than 1. The range of values for $a$ is ( ).
A. $(-1,1)$
B. $(-\infty,-1) \cup(1,+\infty)$
C. $(-2,1)$
D. $(-\infty,-2) \cup(1,+\infty)$
3. C. Let $f(x)=x^{2}+\left(a^{2}-1\right) x+a-2$, then $f(1)<0$.

