In the scenario described, Lexi folded her paper such that point C is on top of point D, which indicates that the fold acts as a line of symmetry between these two points. The point E, where the fold intersects the line segment CD, serves as the midpoint.
Given that the fold line is a line of symmetry, the segment that bisects CD is the line segment QR, which is drawn through point E at an arbitrary angle. This means QR intersects CD at its midpoint, thus acting as the segment bisector for CD.
Therefore, the correct response is:
QR←→