You are taking over the security of an existing network. You discover a machine that is not being used as such, but has software on it that emulates the activity of a sensitive database server. What…

A virus is self-replicating malicious software that infects other programs; it has no function as a decoy or server emulation tool.

A reactive IDS detects intrusions and triggers automatic countermeasures in response; it does not emulate server behavior to attract attackers.

A honeypot is a security deception tool that simulates a legitimate and attractive target - such as a sensitive database server - without serving any real operational purpose. It lures attackers into interacting with the fake system, allowing defenders to observe techniques, gather threat intelligence, and detect intrusions without risking real assets.

A polymorphic virus is malware that mutates its own code to evade signature-based detection; it is an offensive threat, not a defensive decoy system.