Ella is a Scrum Master. She used to attend or facilitate the different Scrum events: sprint, sprint planning, daily standup, sprint review, and sprint retrospective. Which of the following options describes the sprint retrospective meeting? A meeting for refining product backlog items A meeting for defining and evaluating the work of the next sprint A meeting for discussing the negative and positive aspects of a sprint as well as any possible improvements A meeting held at the end of the project's last sprint