The length of a triangle are 8, 12 and $x$. Which of the following inequalities shows all possible values of $x$ ?

Question

$\begin{array}{1 1} (a)\; 8 < x <12 \\ (b)\; 4 \leq x \leq 20 \\ (c)\; 4 < x < 20 \\ (d)\; 4 < x < 12 \end{array}$</span>