What should the team do?

If a story is not completed, it is not counted toward the current sprint velocity. When carrying the story forward to the next sprint, teams should re-evaluate the story size, especially if part of the work is already done. According to the PMI Agile Practice Guide (Section 5.4: Velocity and Estimation) and Mike Griffiths’ PMI-ACP Exam Prep Book (Chapter 6: Adaptive Planning), agile teams are encouraged to re-estimate such items based on remaining work.

Option D is correct: incomplete stories should be re-estimated based on new size or effort.

Option A violates velocity principles—only fully completed stories count.

Option B undermines the fixed-length timebox principle of sprints.

Option C is not directly relevant unless the story’s complexity necessitates research, which is not stated here.