Consider the piecewise function

$f(x)=\{\begin{array}{cc}1,& x>0\\ -1,& x<mn>0</mn>\end{array}$

What is the limit of $f(x)$ as $x$ approaches $-3?$

$\underset{?}{lim}f(x)=-3$

$x-3$

$\underset{?}{lim}f(x)=-1$

$x-3$

$\underset{?}{lim}f(x)=1$

$x-3$

The limit does not exist.