According to the PMBOK® Guide and the Standard for Project Management, the process of confirming resource availability and obtaining the team necessary to complete project activities is Acquire Resources (referred to in previous editions as Acquire Project Team).

This process is part of the Executing Process Group. As per PMI standards, the key benefit of this process is outlining and guiding the selection of resources and assigning them to their respective activities. The internal and external resources required to complete the project are identified and secured during this stage.

The other options are incorrect based on the following PMI definitions:

Plan Human Resource Management: (Now Plan Resource Management) This is the process of defining how to estimate, acquire, manage, and use team and physical resources. It is a Planning process that creates the strategy but does not perform the actual acquisition.

Manage Project Team: (Now Manage Team) This is the process of tracking team member performance, providing feedback, resolving issues, and managing team changes to optimize project performance. It occurs after the team has been acquired.

Develop Project Team: (Now Develop Team) This is the process of improving competencies, team member interaction, and the overall team environment to enhance project performance. Like managing, this happens after the team is already in place.

As per the PMI Lexicon of Project Management Terms, the acquisition of resources often involves negotiation with functional managers and external vendors to ensure the project has the specific skill sets required for success.