Hello!
In our case, a 90 degree rotation will land our figure in either Quadrant 1 or 3. Our final figure is in Quadrant 4. Therefore A and C are not our answers.
The line y=x is diagonal and goes straight across the graph through the origin. This would put our figure in Quadrant 4, put the shape would not be facing the right direction. So B is not our answer.
This leaves us with C. A 180 degree rotation will put our figure in Quadrant 4 and will turn it to match our final figure.
Therefore, our final answer is D. rotation 180° about the origin.
I hope this helps!