CAPM Practice: Demonstrate an understanding of project management planning

A milestone is a significant point or event in the project timeline that has zero duration—it marks the completion of a major deliverable or phase. Task duration is the estimated time period required to complete a specific work activity.

**Why not B:** Milestones and task durations are not differentiated by their unit of measurement. Both can be associated with various time units. The key distinction is that milestones have zero duration as significant points in time, while task durations represent the elapsed time needed to complete work.

**Why not C:** There is no five-day threshold that distinguishes milestones from tasks. A milestone is defined by being a significant point with zero duration, not by exceeding a certain time length. Tasks of any duration remain tasks, not milestones.

**Why not D:** Milestones and task durations are not assigned based on team member seniority. Both are schedule elements defined by their nature — milestones mark key events, while task durations represent work effort — regardless of who is involved.