Which of the following tools is used to verify the network structure packets and confirm that the packets are constructed according to specification?

EtherApe is a graphical Unix network traffic monitor that visualizes active connections and bandwidth usage, not a tool for validating packet construction against protocol specifications.

The Snort decoder is a core preprocessor that dissects network packets layer by layer, verifying that each field is constructed according to protocol specifications. It decodes traffic such as IP, TCP, UDP, and application-layer protocols, flagging anomalies or structural violations that deviate from expected formats before other preprocessors and rules are applied.

AirSnort is a passive wireless tool designed to recover WEP encryption keys by collecting and analyzing enough encrypted packets, with no function related to verifying packet structure conformance.

snort_inline is an operational mode of Snort used for inline traffic inspection and active packet dropping or modification in a bridged network path, not for structural packet validation.