*Question T2C05:
What does the term “traffic” refer to in net operation?*  

*Correct Answer is  A: Messages exchanged by net stations*  

### AI Response: (may contain errors)  

In net operation, the term "traffic" specifically refers to the messages exchanged by net stations. Let's break down the correct answer and the other choices:

### Correct Answer: A - Messages exchanged by net stations
- **Explanation**: In the context of amateur radio nets, "traffic" denotes the actual communications or messages that are being passed between stations. This can include formal messages, updates, or any information that needs to be relayed during the net operation.

### Why the Other Choices are Incorrect:
- **B: The number of stations checking in and out of a net**
  - **Explanation**: While the number of stations participating in a net is important, it does not define "traffic." This choice refers to the participation level rather than the content of the messages exchanged.

- **C: Operation by mobile or portable stations**
  - **Explanation**: This choice describes the type of stations that may be involved in a net but does not pertain to the concept of "traffic." The term "traffic" is focused on the messages, not the operational status of the stations.

- **D: Requests to activate the net by a served agency**
  - **Explanation**: This option refers to the initiation of net operations, often in emergency situations, but it does not relate to the messages exchanged during the net. "Traffic" specifically involves the communication that occurs once the net is active.

### Summary
- **Traffic** = Messages exchanged by net stations (Correct)
- Other choices focus on participation, station type, or activation requests, which do not define "traffic."

Understanding these distinctions will help you grasp the terminology used in net operations and prepare effectively for the Extra Class exam.