The project manager is responsible for determining the appropriate combination of processes, inputs, tools, techniques, outputs and life cycle phases to manage a project. this is referred to as:

project management process

Explanation: A process can be defined as a set of interrelated actions or activities that are carried out in order to achieve a predetermined outcome. The project management process refers to the planning, controlling, and other activities involved in executing a project and achieving the project objectives.

Project management studies can be regarded as the core process that links all the other project activities and processes together. Bigger and more complex projects usually require more formal project management processes. The type of project, the resources available, and the environment in which the project is carried out will all influence the processes that are required to manage a specific project.