Decapsulation

• A. Wrapping data with headers as it travels down the OSI layer
• B. Encrypting data for secure transmission.
• C. Removing a header or trailer from a lower OSI layer.
• D. Assigning IP addresses to hosts.

Answer: (C)

Decapsulation is the process of removing the extra headers and trailers that were added as data moved down the protocol stack. When data is sent, each layer wraps the payload with its own header (and sometimes a trailer) so the network can deliver it properly. When the packet arrives at the destination, the opposite happens: the receiving device strips off the data link header and trailer, then the network header, and so on, as the data moves up to the correct upper-layer protocol. This is exactly described by removing a header or trailer from a lower OSI layer, which is why that choice is the best fit. Wrapping data with headers describes encapsulation (the opposite process), encrypting is about security, and assigning IP addresses is about addressing, not decapsulation.