A self-organizing Development Team is primarily responsible for selecting the work they commit to and executing that work within a Sprint. Pulling Product Backlog items for the Sprint is a crucial responsibility as it allows the team to choose the tasks they will work on based on priority and their capacity. Doing the work planned in the Sprint Backlog is their main operational responsibility, ensuring they deliver potentially shippable increments of the product. Reordering the Product Backlog is typically the responsibility of the Product Owner, and increasing velocity or reporting daily progress to stakeholders are not direct responsibilities of the development team.