The following is an incomplete paragraph proving that ∠WRS ≅ ∠VQT, given the information in the figure where segment UV is parallel to segment WZ.: Segments UV and WZ are parallel segments that intersect with line ST at points Q and R, respectively.

According to the given information, segment UV is parallel to segment WZ, while angles SQU and VQT are vertical angles. Angle VQT is congruent to angle SQU by the Vertical Angles Theorem. Because angles SQU and WRS are angles, they are congruent according to the Angles Theorem. Finally, angle VQT is congruent to angle WRS by the Transitive Property of Equality.

Which term accurately completes the proof?

Alternate interior
Corresponding
Same-side interior
Vertical