$\Delta XYZ$ is a right angled triangle , right angled at Y as shown in figure . What is the value of the difference of $\sin 60^{\circ}$ and $\cos 30^{\circ}$ if the ratio of the sides are $1: \sqrt 3:2$

Question

$\begin{array}{1 1} (a)\; 0 \\ (b)\; 2 \\ (c)\; 1 \\ (d)\; 3 \end{array}$