Final answer:
During the monitoring and controlling phase of a project, the key step is to compare the project's performance against the baseline, which allows the team to measure deviations from the plan and take corrective action.
Step-by-step explanation:
The step performed during the monitoring and controlling process group is (c) Compare results of project performance against the baseline to measure project deviation from the plan. This is because monitoring and controlling involve tracking, reviewing, and regulating the progress and performance of the project. It is essential to identify any areas in which the project may be deviating from the plan so that corrective action can be taken. Other tasks such as creating work breakdown structures or defining project requirements happen during the planning or initiation phases. The turnover of the final deliverables occurs in the closing phase of the project.