Which of the following is the first step in managing projects?

A) Determining participants and stakeholders
B) Defining project objectives and scope
C) Establishing checkpoints
D) Identifying and obtaining necessary resources

Defining project objectives and scope is the first step in managing projects. This involves identifying the goals and requirements of the project, as well as the limitations and boundaries within which it must be completed. Only after this initial planning phase can the other steps, such as determining participants and stakeholders, establishing checkpoints, and obtaining resources, be effectively carried out.