Let $f(x)=\frac{2x^2-7x-4}{x^2+x-20}.$ Find the indicated quantities, $if$ they exist.

$(A)\underset{x4}{lim}f(x)$

$(B)\underset{x0}{lim}f(x)$

$(C)\underset{x1}{lim}f(x)$

$(A)$ Select the correct choice below and, $if$ necessary, fill $in$ the answer box $to$ complete your choice.

$A.\underset{x4}{lim}\frac{2x^2-7x-4}{x^2+x-20}=1(Typean$ integer $or$ a simplified fraction.$)$

$B.$ The $limit$ does not exist.

$(B)$ Select the correct choice below and, $if$ necessary, fill $in$ the answer box $to$ complete your choice.

$A.\underset{x0}{lim}\frac{2x^2-7x-4}{x^2+x-20}=(Typean$ integer $or$ a simplified fraction.$)$

$B.$ The $limit$ does not exist.