According to the PMBOK® Guide, a Responsibility Assignment Matrix (RAM) is a grid that shows the project resources assigned to each work package. It is used to illustrate the connections between work packages or activities and project team members.

The RAM and RACI: A common example of a RAM is the RACI chart (Responsible, Accountable, Consulted, and Informed).

Responsible: The person who performs the work.

Accountable: The person with ultimate decision-making authority (only one per task).

Consulted: People whose opinions are sought.

Informed: People who are kept up-to-date on progress.

Purpose: The RAM ensures that there is clear assignment of responsibility for every task in the group, preventing confusion about who is doing what. On larger projects, RAMs can be developed at various levels (e.g., high-level for groups/units and low-level for specific individuals and tasks).

Integration: It bridges the gap between the work (WBS) and the people (OBS).

Analysis of Other Options:

A. Work breakdown structure (WBS): This is a deliverable-oriented hierarchical decomposition of the work to be executed. While it defines the tasks/deliverables, it does not inherently show the people or roles assigned to them.

C. Organizational breakdown structure (OBS): This is a hierarchical representation of the project organization, which illustrates the relationship between project activities and the organizational units that will perform those activities. It focuses on the organizational hierarchy, not the mapping of roles to specific tasks.

D. Resource breakdown structure (RBS): This is a hierarchical list of team and physical resources related by category and resource type. It is used for planning and controlling project work, but it lists what resources are available, not who is assigned to which specific task.