What should the product owner do to resolve this?

When significant architectural flaws are discovered, agile teams inspect and adapt. According to the PMI Agile Practice Guide (Section 5.6: Retrospectives and Adaptation), the product owner and team should collaboratively reassess priorities and rewrite backlog items to reflect the rework needed. This is aligned with agile’s incremental delivery and continuous adaptation.

Mike Griffiths in the PMI-ACP Exam Prep Book (Chapter 6: Adaptive Planning) stresses that rework should be handled through backlog refinement and collaborative planning—not panic or reactive decisions.

Option C is correct: reassessing the backlog with stakeholders aligns with agile practices.

Option A abdicates product responsibility.

Option B is too rigid for agile, unless the risk matrix is already very mature and agile-focused.

Option D cancels value delivery and is unnecessarily drastic.