What is the role of the investigator in the research project?

The investigator is usually present during the planning stage of the research project, i.e., in the elaboration of the research project.
The investigator is the one who receives and designs the characteristics and stages that the research project must fulfill.
The people who wear white coats and manipulate laboratory instruments are usually assistants who have little or nothing to do with the conception of the research.
All of the above.