Once a Sprint begins, its committed scope and Acceptance Criteria are normally protected from change. New requirements are ordinarily added to the Prioritized Product Backlog and considered in a later Sprint. However, SBOK defines an important exception: if a change is so significant that continuing the existing Sprint would no longer create meaningful or useful results, the active Sprint should be terminated and a new Sprint planned using the revised requirements.

The scenario explicitly describes a critical business requirement that changes the Acceptance Criteria governing committed work. This implies that the existing Sprint outcome may no longer satisfy the customer's essential need. In that situation, simply continuing against obsolete criteria would waste resources.

Option A allows uncontrolled mid-Sprint scope substitution, which Scrum avoids. Option B would normally be correct for a non-urgent change, but the question emphasizes criticality. Option C incorrectly frames the problem as team bandwidth rather than Sprint stability and business value.

Therefore, where the changed requirement invalidates the current Sprint's intended outcome, Sprint termination and replanning is the appropriate response.

Study Guide reference: Change - > Integrating Change; Maintaining Sprint Stability; Managing Urgent Change Requests.

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