*Question E2C11:
How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?*  

*Correct Answer is  A: Send your full call sign once or twice*  

### AI Response: (may contain errors)  

To identify your station when attempting to contact a DX station during a contest or in a pileup, the correct approach is to:

**Correct Answer: Send your full call sign once or twice.**

### Explanation of the Correct Answer:
- **Clarity and Recognition**: Sending your full call sign once or twice ensures that the DX station can clearly identify who is calling. This is crucial in a noisy environment like a contest or pileup where many stations are trying to make contact simultaneously.
- **Regulatory Compliance**: FCC regulations require that you identify your station with your full call sign. This practice helps maintain proper communication protocols.

### Why the Other Choices are Incorrect:
- **Choice B: Send only the last two letters of your call sign until you make contact**  
  - **Issue**: This method is not effective for identification. The DX station may not recognize your call sign, leading to confusion and missed contacts. It also does not comply with FCC regulations.
  
- **Choice C: Send your full call sign and grid square**  
  - **Issue**: While providing your grid square can be useful information, it is not necessary for initial identification. In a pileup, the priority is to get your call sign across quickly and clearly. Adding extra information can lead to delays and confusion.
  
- **Choice D: Send the call sign of the DX station three times, the words “this is,” then your call sign three times**  
  - **Issue**: This method is overly complex and time-consuming in a contest or pileup situation. It can lead to congestion and may not allow for effective communication. The DX station is primarily interested in hearing your call sign to establish contact.

### Rules of Thumb:
- **Keep It Simple**: In a contest or pileup, simplicity is key. Identify yourself clearly and concisely.
- **Follow Regulations**: Always use your full call sign to comply with FCC rules.
- **Be Patient**: If the DX station does not respond immediately, continue to listen and be ready to repeat your call sign as needed.

By following these guidelines, you can improve your chances of successfully making contact during a contest or pileup.