In Scrum and other agile frameworks, the product owner is responsible for managing the product backlog and prioritizing work based on business value. If new requirements arise, they should not be added mid-sprint.
Instead, they should be assessed, prioritized, and-if accepted-incorporated into planning for the next sprint.
According to the Agile Practice Guide and Scrum Guide, the Sprint Backlog is frozen during a sprint to maintain focus and stability. The Product Owner can then introduce new tasks during the next planning session.
Option A and B violate Scrum principles by modifying the sprint backlog mid-sprint.
Option C reflects a predictive approach that is inappropriate in Agile settings.
References:
Agile Practice Guide, Section 3.1 - Role of the Product Owner
The Scrum Guide (Scrum.org), Sprint Planning and Product Backlog sections
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