Answer:
Reflection
Step-by-step explanation:
A rotation would be to rotate a figure around the origin
A reflection would be to reflect the figure around one of the axes.
A translation would be to move a figure a certain amount of units.
Since A and A' are 2 units away from the y-axis, and C, B, B', and C' are all one unit away from the y-axis, this could not be a translation because the position of A'B'C' is not the same position of ABC.
It could not be a rotation around the origin or any point because it would result the figure in either Quadrant 2 or 3, and in the one occasion it would be in Quadrant 1, the figure cannot be in that position.
This reveals only one option, that which is a reflection. A reflection about the x-axis would not make sense, since it would result in Quadrant 3, so a reflection around the y-axis would make the most sense.
The data we have above also accounts for a reflection, since all points are a certain distant away from the y-axis.
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