In project management, what tool is crucial for managing changes to requirements?

The requirements management plan is essential for managing changes to requirements because it outlines how requirements will be identified, documented, analyzed, prioritized, tracked, and communicated throughout the project lifecycle. This plan provides a clear framework that helps stakeholders understand how changes will be handled, which ensures consistency and control over requirements modifications.

Having a well-defined requirements management plan is critical for maintaining project scope and aligning with stakeholder expectations. It can include procedures for how changes are requested, evaluated, and approved, ultimately facilitating effective requirement validation and ensuring that all necessary changes are adequately captured and documented.

Other options like the project schedule, change control log, and risk register also play roles in project management but do not focus specifically on the management of requirements. The project schedule primarily deals with timelines and deliverables, while the change control log tracks changes that have been approved and their impacts on the project, not necessarily on requirement changes alone. The risk register focuses on identifying potential risks and their mitigation strategies, which is a different area of project management.