Which of the following statements is true regarding Ethernet frames?

Ethernet frames are structured to include both a header and a trailer. The header is essential because it contains critical information such as source and destination MAC addresses, which are used for addressing the frames at the data link layer. This allows devices on the same local area network (LAN) to identify and communicate with each other effectively.

The trailer, which typically contains the Frame Check Sequence (FCS), is used for error detection. The FCS helps ensure that the frame has not been corrupted during transmission, allowing the receiving device to confirm whether the data received is intact or has experienced any errors.

The other options present inaccuracies about the composition and capabilities of Ethernet frames. Stating that Ethernet frames do not have a trailer is incorrect because the trailer is an integral part of the frame. The claim that frames only contain payload data ignores the critical components of the header and trailer that provide necessary context and error-checking. Moreover, the assertion that Ethernet frames can only support IPv4 is misleading, as Ethernet can encapsulate various Layer 3 protocols, including IPv6. Thus, stating that Ethernet frames contain both a header and trailer is the most accurate representation of their structure.