What is the best description of PMI?

PMI stands for Project Management Institute, which is a global non-profit professional organization for project managers. PMI provides a range of resources, tools, and training to help project managers advance their careers and improve their skills. One of PMI's most well-known contributions to the field of project management is the Project Management Body of Knowledge (PMBOK), which is a guide that outlines standard project management practices and processes. PMI also offers a range of certifications for project managers, including the Project Management Professional (PMP) certification, which is widely recognized as a mark of excellence in the field. Overall, PMI plays an important role in promoting the profession of project management and helping project managers succeed in their careers.