*Question E2C02:
Which of the following file formats is used for exchanging amateur radio log data?*  

*Correct Answer is  C: ADIF*  

### AI Response: (may contain errors)  

The correct answer is **C: ADIF**.

1. **Why the correct answer is correct:**
   - **ADIF (Amateur Data Interchange Format)** is a standardized file format used by amateur radio operators to exchange log data between different logging software. It is widely accepted and allows for easy transfer of contact information, such as call signs, frequencies, and modes, between different systems.

2. **Why the other choices are incorrect:**
   - **A: NEC** - This stands for Numerical Electromagnetics Code, which is a software tool used for antenna modeling and design, not for exchanging log data.
   - **B: ARLD** - This is not a recognized file format for log data exchange. It might be confused with ARRL (American Radio Relay League) bulletins, but it is not related to log data.
   - **D: OCF** - This stands for Off-Center Fed, typically referring to a type of antenna, not a file format for log data.

3. **Useful Information:**
   - When preparing logs for contests or awards, using ADIF ensures compatibility across different logging programs, making it easier to submit logs to contest organizers or upload them to online databases like Logbook of The World (LoTW).