The Sprint Backlog is collectively owned by the Developers, not assigned to individuals. The Scrum Guide defines it as: 'The Sprint Backlog is a plan by and for the Developers... It is a highly visible, real-time picture of the work that the Developers plan to accomplish during the Sprint.' Self-organization means the Developers decide who does what, without fixed ownership of items.

A, B: Individual assignment isn't mandated; it's a team effort.

C: Correct---the Developers as a whole own it.

D: The Product Owner manages the Product Backlog, not the Sprint Backlog.

Exact Extract from Scrum Guide: 'The Sprint Backlog is a plan by and for the Developers. It is composed of the Sprint Goal (why), the set of Product Backlog items selected for the Sprint (what), as well as an actionable plan for delivering the Increment (how).' (Section: 'Sprint Backlog')

Thus, C is correct.