Answer:
D) Dilation and reflection.
→ The shape was dilated by -1.
→ This shape was then reflected upside down.
Dilation
Dilating a shape is the act of making a shape smaller by a scaled amount. Dilation is useful in mathematics when you need to determine difference in shapes' scales factors.
Reflection
Reflection is mirroring a shape to its opposite image. For instance, I have triangle ∠ABC', which is facing right. I then reflect this image, and it becomes triangle ∠ABC", which now faces left on the opposite axis.