According to the PMBOK® Guide, the Project Cost Management knowledge area consists of the processes involved in planning, estimating, budgeting, financing, funding, managing, and controlling costs so that the project can be completed within the approved budget.

In the standard lifecycle (such as in PMBOK® Guide 5th and 6th Editions), there are three core processes:

Estimate Costs: The process of developing an approximation of the monetary resources needed to complete project work.

Determine Budget: The process of aggregating the estimated costs of individual activities or work packages to establish an authorized cost baseline.

Control Costs: The process of monitoring the status of the project to update the project costs and managing changes to the cost baseline.

Analysis of Other Options:

A. Estimate Costs, Control Schedule, and Control Costs: Control Schedule belongs to the Project Schedule Management knowledge area, not Cost Management.

B. Estimate Costs, Determine Budget, and Estimate Activity Resources: Estimate Activity Resources is traditionally a process within Project Schedule Management (or Project Resource Management in newer editions).

C. Determine Budget, Control Schedule, and Estimate Activity Resources: This option incorrectly includes processes from both Schedule and Resource Management.