Final answer:
Development Team members take ownership of a Sprint Backlog item during the Sprint Planning meeting. During this time, they commit to the items they will work on in the upcoming Sprint.
Step-by-step explanation:
Development Team members take ownership of a Sprint Backlog item during the Sprint Planning meeting. This is a ceremony in Scrum, an Agile framework for completing complex projects. During Sprint Planning, the Product Owner presents the priority items from the Product Backlog, and then the Development Team selects the items they can commit to completing during the upcoming Sprint, thus taking ownership of them. The Development Team self-manages and self-organizes to determine the best way to accomplish this work, often through discussion and consensus within the team.