Where may you add the most impactful improvements of the Retrospective?
I'm preparing myself to PSM2 certification test and found this mock question online with the correct marked as:
To the Sprint Backlog of the next Sprint.
I answered Product Backlog.
My reasoning is that everything that comes from either the Review or the Retro is added there, and only on the Planning the Scrum Team checks what should be done, based on the Sprint Goal and the value order of the PBI's.
Am I wrong? Should it be mandatory to have "the most impactful improvement" on the next Sprint Backlog?
There is a direct answer for this in Sprint Retrospective part in Scrum Guide,
The Scrum Team identifies the most helpful changes to improve its effectiveness. The most impactful improvements are addressed as soon as possible. They may even be added to the Sprint Backlog for the next Sprint.
improvement is not something you identify now and act later.
My reasoning is that everything that comes from either the Review or the Retro is added there,
Why? Why should every end-of-Sprint adaptation be left to the Product Owner to manage?
The 2017 Scrum Guide was prescriptive mentioning that at least one improvement should be added to the Sprint Backlog. This was removed in the Nov 2020 version. Perhaps your mock online isn't up to date?