Explanation
According to the PMBOK Guide, the project manager is responsible for managing the project knowledge by creating, organizing, and transferring knowledge among project stakeholders. One of the tools and techniques for managing project knowledge is knowledge repositories, which are systems or databases that store and organize project information and lessons learned. Knowledge repositories can help the project manager and the project team access and use the knowledge generated throughout the project life cycle, as well as leverage the knowledge from previous projects. In this scenario, an agile senior project team member suddenly resigns from the organization, leaving a knowledge gap in the project team. The remaining team members are having difficulty accessing information and are unable to complete a deliverable. This situation could have been avoided if the project manager had ensured the project repository is up to date, using knowledge repositories as a tool. This option could have helped the project manager capture and document the knowledge of the senior project team member before they left, and make it available and accessible for the rest of the team. This could have prevented the loss of critical information and enabled the team to complete the deliverable.
Updating the job descriptions, making an effort to reemploy the senior project team member, or providing specialist training are not the best options, as they do not address the issue of knowledge management, or may be too late or impractical to implement. References: PMBOK Guide, 7th edition, pages 233-234, 13.2 Manage Project Knowledge.