Answer:
Rotation
Step-by-step explanation:
If you were to translate it, it wouldn't match up because it needs to be turned around. translation just involves moving the shape without rotating it. a dilation means that you're changing the size, and you're not supposed to do that for this problem. a reflection means that if you were to fold in between these two shapes, they would match up. They Don't in this case so that won't work. A rotation is the only way to get it so that all of the areas match up.