The navigation message includes information about which aspects?

• A. Only the satellite ephemeris
• B. Only system health
• C. Status of both the satellite and the system as a whole
• D. Weather data

Answer: (C)

Navigation messages carry the data needed to compute your position and to monitor system integrity. Each satellite’s ephemeris is transmitted, giving the precise orbital parameters that let your receiver determine where the satellite is in space. At the same time, the message includes health information—flags about the status of individual satellites and the overall system—so receivers can assess whether a satellite is functioning properly or if there are system-wide issues. Weather data is not part of the navigation message, so the information you get focuses on where the satellites are and how healthy the system is. That combination is why the best answer is that the message provides the status of both the satellite and the system as a whole.