CAPM Practice: Demonstrate an understanding of project management planning

The cost baseline is the approved time-phased budget used to measure, monitor, and control overall cost performance on the project. It serves as the reference point against which actual costs are compared.

**Why not A:** Documenting all potential expenses including contingency and management reserves describes the overall project budget, not the cost baseline specifically. The cost baseline excludes management reserves — it includes only the authorized budget for performing project work plus contingency reserves.

**Why not B:** Providing detailed cost estimates for individual work packages is the output of cost estimating, which feeds into the cost baseline but is not its primary purpose. The cost baseline aggregates these estimates into a time-phased budget used for performance measurement.

**Why not C:** Justifying the business case and ROI is the purpose of the business case document created during project initiation. The cost baseline is a performance measurement tool used during execution, not a justification document for senior management.