Final answer:
The student's question is about the sequence of rigid transformations that resulted in polygon A'B'C'D' from polygon ABCD. While the reflections lines are unspecified, typically two reflections across intersecting lines equal a rotation around the point of intersection by twice the angle between the lines.
Step-by-step explanation:
The student's question involves identifying the type of rigid transformations that polygon ABCD underwent to form polygon A'B'C'D'. Unfortunately, there seem to be missing elements in the provided description of the transformations. Normally, a rigid transformation would include details such as the lines across which the reflections occur. That said, a sequence of two reflections across two intersecting lines is equivalent to a rotation around the point of intersection of the lines, with the angle of rotation being twice the angle between the two lines.
If we could infer that the lines of reflection are perpendicular to each other, the overall transformation would be a rotation of 180 degrees. This would mean that polygon A'B'C'D' is the result of this 180-degree rotation of polygon ABCD about the point of intersection of the two reflection lines.