I was expecting a choice that said A(1,4) is in the first quadrant so 90 degrees clockwise is fourth quadrant. For perpendicularity we reverse the coordinates, negating one of them. For the fourth quadrant, it must be the y coordinate that's negative. We end up at A'(4,-1).
The answer is the second choice: create a circle with the center at the origin. The image of A' will be on the circle, 90 degrees clockwise from A.
