Which major NIMS component describes systems and methods that help to ensure that incident personnel and other decision makers have the means and information they need to make and communicate decisions?

The major NIMS component that describes systems and methods ensuring incident personnel and other decision makers have the means and information needed to make and communicate decisions is “Communications and Information Management.”

Communications and Information Management supports the integration of communication tools, technologies, and methods to allow for the seamless exchange of information. For example, during a large-scale natural disaster, this component would enable emergency managers, response teams, and government agencies to share situational reports, resource requests, and status updates efficiently. By doing so, it ensures that decision-makers at all levels have a comprehensive understanding of the incident, which is critical for strategizing response efforts, deploying resources effectively, and minimizing the impact of the incident on affected communities. 

Source: https://training.fema.gov/emiweb/is/is200c/english/instructor%20guide/is0200c%20ig.pdf