According to the PMBOK® Guide and the Standard for Project Management, specifically within the Create WBS process of the Project Scope Management Knowledge Area, the planned work contained in the lowest-level components of the Work Breakdown Structure (WBS) is known as Work packages.
As per PMI standards, a WBS is a hierarchical decomposition of the total scope of work to be carried out by the project team to accomplish the project objectives and create the required deliverables. A Work package is unique because:
Estimating and Managing: It represents the level at which cost and duration can be reliably estimated and managed.
Accountability: It can be assigned to a specific individual or organizational unit for execution.
Control Accounts: Work packages are grouped into " Control Accounts, " which are management control points where scope, budget, and schedule are integrated and compared to the earned value for performance measurement.
Decomposition: While a WBS can have many levels, the " Work Package " is the terminal point of that decomposition.
The other options are incorrect based on the following PMI definitions:
Accepted deliverables: These are the outputs of the Validate Scope process that have been formally signed off by the customer or sponsor. They are results, not the " planned work components " of the WBS itself.
The WBS dictionary: This is a Project Document that provides detailed deliverable, activity, and scheduling information about each component in the WBS. It supports the WBS but is not the component itself.
The scope baseline: This is an integrated component of the project management plan that includes the Project Scope Statement, the WBS, and the WBS Dictionary. It is the " parent " container of the WBS, not the lowest-level component.
As per the PMI Lexicon of Project Management Terms, the work package is the smallest unit of the WBS and serves as the foundation for defining activities in the Define Activities process.
