Answer:
"A translation 5 units down, followed by a 180-degree counterclockwise rotation about the origin"
Explanation:
since the choices all have rotation about the origin, we must shift the original triangle in a suitable position. This is done by connecting any of the points of A'B'C' to the origin, and extend this line segment, as shown in the picture.
The most appropriate point is C', and we draw C" such that C'O=OC", and C', O and C" are collinear.
We see that the distance CC'' is 5.
So
Answer is:
"A translation 5 units down, followed by a 180-degree counterclockwise rotation about the origin"