Explanation
= According to the PMBOK Guide, a change request is a formal proposal to modify any document, deliverable, or baseline. A change request can be initiated by any stakeholder involved with the project, and it must be reviewed and approved by the CCB. The CCB is a formally chartered group responsible for reviewing, evaluating, approving, delaying, or rejecting changes to the project, and for recording and communicating such decisions. In this scenario, the project manager should submit a change request to the CCB as soon as possible, as the delay in the delivery of the key component will affect the project schedule and scope. The project manager should also update the project management plan and other relevant documents to reflect the impact of the change. Asking the vendor for the minimally sufficient materials, performing market research for other vendors, or involving the legal department are not the best options, as they may not resolve the issue in time, incur additional costs, or escalate the conflict with the vendor. References: = PMBOK Guide,
6th edition, pages 112-114, 123-124, 140-141.