The correct answer is D. 10 or fewer. According to the Scrum Guide 20201, "The Scrum Team is small enough to remain nimble and large enough to complete significant work within a Sprint, typically 10 or fewer people." The other options are outdated or incorrect. Option A was based on the previous version of the Scrum Guide, which suggested a range of 3 to 9 developers2. Option B is too vague and does not account for the upper limit of team size. Option C is too specific and does not allow for flexibility.

According to the Scrum framework, the Product Owner is responsible for managing the Product Backlog, which includes prioritizing and adding new items1. However, when a new item is introduced during a Sprint, it is crucial to involve the entire Scrum Team in the decision-making process. This ensures that the team can assess the impact of the new item on the current Sprint goals, capacity, and workload1. By discussing the item with the team, they can collectively decide whether to include it in the current Sprint, defer it to a future Sprint, or handle it in another way1. This collaborative approach aligns with the principles of transparency, inspection, and adaptation, which are core to Scrum.

When many Development Teams are working on a single product, the definition of "Done" must be shared by all Development Teams and make their combined work potentially releasable, as stated in [4]: "When multiple teams work together on one product they must mutually define and comply with the same Definition of Done. This makes sure all Increments adhere to a consistent quality level."

According to the Scrum Guide, changing the terminology of Scrum may have negative consequences, such as losing the benefits of Scrum, not understanding what has changed, or having very little change at all. Therefore, all answers apply to this question. The Scrum Guide recommends using the same terminology as in the guide to avoid confusion and misunderstanding.