*Question G8C03:
What part of a packet radio frame contains the routing and handling information?*  

*Correct Answer is  C: Header*  

### AI Response: (may contain errors)  

In packet radio communication, a data packet is structured into several parts, each serving a specific purpose. Understanding these parts is crucial for identifying where specific information is stored.

### Explanation:

1. **Correct Answer: Header**
   - The **header** of a packet radio frame contains the routing and handling information. This part of the packet includes details such as the source and destination addresses, packet type, and any other control information necessary for the packet to be properly routed and processed through the network.

2. **Why the Other Choices are Incorrect:**
   - **A: Directory**  
     - A directory is not a part of a packet radio frame. It typically refers to a file system structure or a list of files, not a component of data packets.
   - **B: Preamble**  
     - The preamble is used for synchronization purposes. It helps the receiving station recognize the start of a new packet by providing a known pattern to lock onto, but it does not contain routing or handling information.
   - **D: Trailer**  
     - The trailer, often called the footer, is found at the end of the packet. It usually contains error-checking information, such as a checksum or CRC (Cyclic Redundancy Check), to ensure data integrity, but it does not include routing information.

### Key Points:
- **Header**: Contains routing and handling information.
- **Preamble**: Used for synchronization.
- **Trailer**: Contains error-checking information.

Understanding the structure of a packet and the role of each part is essential for troubleshooting and optimizing packet radio communications.