If two angles of $\Delta ABC$ are $45^{\circ}$ and $60^{\circ}$, then the ratio of the smallest and the greatest sides are

Question

\[\begin {array} {1 1} (a)\;(\sqrt 3-1):1 & \quad (b)\;\sqrt 3:\sqrt 2 \\ (c)\;1:\sqrt 3 & \quad (d)\;\sqrt 3:1 \end {array}\]