Answer:
1 to 2.
We can see that the figure starts at the bottom left, and then moves to the bottom right.
So the vertical position remains constant, and the horizontal position changed, this can be a reflection around the vertical axis.
2 to 3.
Now the figure goes from the bottom right and moves to the top right, not only that, in (2) the figure is facing up, and in (3) the figure is facing down, then we have a reflection around the horizontal axis.
3 to 4.
Similar to the first case, this is a reflection over the vertical axis.
4 to 5.
Similar to the second case, this is a reflection over the horizontal axis.
(Something to notice, the movements can be called "Rotations over the ___ axis". I used reflection because it is specific for this type of motion, while rotation can be used to describe really complex types of motion)