Deviation from a mitigation action plan’s completion date should be determined by the risk owner as determined by risk management processes, because the risk owner is the person or entity who has the accountability and authority to manage the risk and its associated mitigation actions. The risk owner should monitor and report the progress and status of the mitigation action plan, and determine if there is any deviation from the expected completion date, based on the risk management processes and criteria. The other options are not the ones who should determine the deviation, because:

Option A: Change management as determined by a change control board is a process that ensures that any changes to the project scope, schedule, cost, or quality are controlled and approved, but it does not determine the deviation from the mitigation action plan’s completion date, which is a risk management activity.

Option B: Benchmarking analysis with similar completed projects is a technique that compares the performance and practices of the current project with those of similar or successful projects, but it does not determine the deviation from the mitigation action plan’s completion date, which is a risk management activity.

Option C: Project governance criteria as determined by the project office is a set of rules and standards that define the roles, responsibilities, and authority of the project stakeholders, but it does notdetermine the deviation from the mitigation action plan’s completion date, which is a risk management activity. References = Risk and Information Systems Control Study Manual, 7th Edition, ISACA, 2020, p. 122.