Final answer:
The transformation rule (x, y) ⟶ (-y, x) results in a rotation of 90 degrees counterclockwise over the origin.
Step-by-step explanation:
The transformation rule described in the question (x, y) ⟶ (-y, x) corresponds to a rotation in the coordinate system. To understand which rotation it is, consider a point (x, y) and imagine applying the rule to find the new coordinates. Since the x-coordinate becomes the negative y-value, and the y-coordinate becomes the x-value, we can deduce that the point has been rotated 90 degrees counterclockwise around the origin. In the coordinate system, positive rotations are typically in the counterclockwise direction and negative rotations are in the clockwise direction. Therefore, the correct answer is B) Rotation 90 degrees counterclockwise over the origin.