Which of the following is NOT an example of passive footprinting?

Scanning ports requires establishing direct network communication with the target host to probe for open services and running applications. This direct interaction makes it an active footprinting method that can be detected or logged by the target, distinguishing it from passive methods that never contact the target system.

Analyzing job postings is passive footprinting because the attacker reads publicly available information without interacting with or contacting the target organization's systems.

Querying search engines is passive footprinting because it retrieves publicly indexed information from a third-party service, never sending any traffic to the target.

Performing a WHOIS query is passive footprinting because it queries a public registration database maintained by a registrar, not the target system itself.