The project manager should have kept documentation in the PMIS and shared it with appropriate stakeholders. The PMIS is an information system consisting of the tools and techniques used to gather, integrate, and disseminate the outputs of project management processes1. It is used to support all aspects of the project from initiating through closing, and can include both manual and automated systems1. By keeping documentation in the PMIS, the project manager can ensure that the project information is updated, consistent, accessible, and secure. The project manager can also use the PMIS to communicate and collaborate with the relevant stakeholders, such as the project team, the sponsor, the customer, and the auditors2.

Option A is not the best answer because reviewing the risk register to identify a response plan for the audit is a reactive and not a proactive way to handle documentation for the project. The project manager should have anticipated and planned for the audit as part of the project risk management process3.

Option B is not the best answer because assigning a project team member to ensure all project documentation was updated is not a sufficient or efficient way to handle documentation for the project. The project manager should have established a clear and consistent process for updating and maintaining the project documentation, and used the PMIS to facilitate and automate this process4.

Option C is not the best answer because updating the project management plan regularly and having it securely shared with all stakeholders is only a partial way to handle documentation for the project. The project management plan is a formal, approved document that defines how the project is executed, monitored, and controlled. It is an important part of the project documentation, but not the only one. The project manager should have also updated and shared other project documents, such as the project schedule, the project budget, the project status reports, and the project deliverables. References: 1: PMBOK Guide, 7th Edition, Section 4.1.3.2, Project Management Information System 2: PMBOK Guide, 7th Edition, Section 10.1.3.3, Communication Methods, Models, and Channels 3: PMBOK Guide, 7th Edition, Section 11.1.3.1, Risk Management Plan 4: PMBOK Guide, 7th Edition, Section 4.4.3.1, Project Documents Updates : PMBOK Guide, 7th Edition, Section 4.1.3.1, Project Management Plan : PMBOK Guide, 7th Edition, Section 4.1.4.1, Project Documents