A bar with an orange dot near one end turns about its centre by the same angle each time. Which figure comes next?

The dot shows which end is which: the bar turns $135^{\circ }$ anticlockwise each step (dot right, upper-left, bottom, upper-right). One more such turn puts the bar flat with the dot on the left: (a). (b) has the bar flat but the dot on the wrong end, and (d) turns clockwise.