Why should the Product Owner be present at the Daily Scrum?

The correct answer is A, because the Product Owner does not need to be present at the Daily Scrum. The Scrum Guide states that “the Daily Scrum is a 15-minute time-boxed event for the Development Team to synchronize activities and create a plan for the next 24 hours. … The structure of the meeting is set by the Development Team and can be conducted in different ways if it focuses on progress toward the Sprint Goal.” Therefore, the Daily Scrum is an internal event for the Development Team, and the Product Owner can attend only if invited by the Development Team.