The correct answer is C - Ask the team to determine how to adapt to this increase in the next retrospective.
The retrospective is the ideal agile forum to inspect and adapt. It allows the team to identify root causes of issues (such as rising defects), reflect on their quality practices, and collaboratively propose solutions like adding more testing, refining definitions of done, or changing working agreements.
PMI Agile Practice Guide:
"Teams should use retrospectives to analyze quality issues, adapt processes, and commit to continuous improvement." (PMI Agile Practice Guide, Section 5.8 - Retrospectives) Mike Griffiths:
"Quality issues like increasing defect rates should be addressed through team introspection and adaptation in retrospectives, not by command-style fixes." (PMI-ACP Exam Prep, Chapter 7 - Continuous Improvement) Incorrect options:
* A is reactive and bypasses team collaboration.
* B encourages unsustainable practices.
* D disrupts the team's current sprint focus and contradicts agile flow.