Which of the following applications cannot proactively detect anomalies related to a computer?

A host-based firewall monitors and filters traffic to and from the specific computer, allowing it to detect and block suspicious connection patterns directed at that machine.

NIDS operates by inspecting packets flowing across the network segment and has no visibility into host-internal behavior such as file system changes, running processes, or local resource usage. Because it lacks access to the individual computer's internals, it cannot proactively detect anomalies that originate or exist solely on that host.

HIDS (Host Intrusion Detection System) is installed directly on the computer and monitors system calls, file integrity, and logs, giving it the ability to proactively detect host-level anomalies.

An anti-virus scanner actively scans files, memory, and processes on the host computer, enabling it to proactively identify malicious activity on that specific machine.