CAPM Practice: Demonstrate an understanding of a project management plan schedule

Mandatory dependencies are inherent to the nature of the work (e.g., you cannot pour concrete before building the form) or required by contract or regulation. They cannot be changed by the project team regardless of preference. Discretionary dependencies, by contrast, are based on best practice or preference and CAN be modified if needed for schedule compression.

**Why not A:** Dependencies defined by the project team based on best practice are discretionary (preferential) dependencies, not mandatory ones. Discretionary dependencies can be modified or removed if the team decides to work differently or needs to compress the schedule.

**Why not B:** Dependencies from one project to another within a program are external dependencies. While they may constrain scheduling, they are categorized separately from mandatory dependencies, which are inherent to the nature of the work itself.

**Why not D:** Dependencies that can be reordered based on team preference are discretionary dependencies by definition. Mandatory dependencies cannot be changed regardless of team preference because they are dictated by the physical nature of the work or by contractual and regulatory requirements.