Which statement best describes telemetry?

• A. Telemetry is the automatic measurement and transmission of data from remote sensors to a receiver for monitoring.
• B. Telemetry is sending commands from the ground to a remote system.
• C. Telemetry is a method of encrypting data during transmission.
• D. Telemetry is a storage format used in ground stations.

Answer: (A)

Telemetry is the automatic measurement and transmission of data from remote sensors to a receiver for monitoring. Sensors collect values such as temperature, pressure, or position, encode them, and send them over a communications link to a ground or central receiver where operators can monitor and analyze the system in real time. This focus on gathering data from distant locations and delivering it for observation is what distinguishes telemetry from the other ideas: sending commands from the ground is about controlling the remote system, encryption is about protecting data, and storing data describes how information is kept after collection rather than how it is collected and transmitted.