*Question E1D01:
[97.3] What is the definition of telemetry?*  

*Correct Answer is  A: One-way transmission of measurements at a distance from the measuring instrument*  

### AI Response: (may contain errors)  

Telemetry is a term used in communications to describe the process of transmitting data from a remote location to a receiving station. Let's break down the choices:

1. **Correct Answer: A**  
   - **One-way transmission of measurements at a distance from the measuring instrument**  
     - This is the correct definition of telemetry. It involves sending data, such as measurements or readings, from a remote instrument to a receiver without expecting a response. This is typically used in applications like weather stations, space probes, and remote sensors.

2. **Why the other choices are incorrect:**

   - **Choice B: Two-way transmissions in excess of 1000 feet**  
     - This choice is incorrect because telemetry specifically refers to one-way communication, not two-way. The distance mentioned is irrelevant to the definition of telemetry.

   - **Choice C: Two-way transmissions of data**  
     - This is incorrect because telemetry is not about two-way communication. It is solely about sending data in one direction, from the measuring instrument to the receiver.

   - **Choice D: One-way transmission that initiates, modifies, or terminates the functions of a device at a distance**  
     - This describes remote control or command functions, not telemetry. Telemetry is about sending measurement data, not controlling devices.

In summary, telemetry is focused on the one-way transmission of measurement data from a remote location to a receiver, which is why choice A is the correct answer.