A windmill on a canal bank has three blades: one pointing up-right, one up-left and one down-left. Which panel is its image in the canal?

Turn the picture upside down without swapping sides: the tower hangs down from the top, the blades point down-right, down-left and up-left, and the blue door is at the top: (a). (d) swaps left and right, (b) is the windmill itself, and (c) does both.