TheSprint Reviewis heldonce at the end of every Sprint. It is a time-boxed event where the Scrum Team and stakeholders collaborate to inspect the Increment, review progress toward the Product Goal, and adapt the Product Backlog as needed.

According to the2020 Scrum Guide:

The purpose of the Sprint Review is to discuss what was completed during the Sprint and what could be done next to optimize value delivery.

It occursonce at the end of every Sprint, ensuring transparency and stakeholder involvement.

Why the other options are incorrect:

B. One in the middle and one at the end of every Sprint:The Sprint Review is not conducted multiple times within a Sprint.

C. Once at the beginning of the Sprint:The Sprint Review is held at the end of the Sprint, not the beginning.

D. Daily:The Sprint Review is not a daily event. TheDaily Scrumoccurs daily.