Which of the following terms is used to describe a major deliverable or key even in the project used to measure project progress?

Project life cycle describes the entire sequence of phases a project passes through from initiation to closure, not a single measurable event.

A phase is a defined collection of related project activities that culminates in a deliverable, representing a time period rather than a specific measurable point.

Achievement is not a recognized project management term in standard frameworks like PMBOK or CompTIA Project+.

A milestone marks a significant point in a project schedule, such as the completion of a major deliverable or phase gate, and is used specifically to track and communicate project progress. Unlike tasks, milestones have no duration - they represent a moment in time that signals something important has been achieved. This term is standardized in both PMI's PMBOK Guide and CompTIA Project+ curricula.