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

Querying a search engine retrieves publicly indexed information without any direct contact with the target system, which is a classic passive footprinting technique.

Analyzing job postings is a passive technique that extracts clues about a target's technology stack and infrastructure from publicly available recruitment data.

Port scanning directly transmits network packets to the target system to enumerate open ports and running services, constituting active footprinting. Active footprinting involves direct interaction with the target, which can leave traces in logs and trigger intrusion detection systems, unlike passive methods that rely solely on publicly available information.

A WHOIS query retrieves publicly registered domain and IP ownership data from public registrar databases without directly probing or interacting with the target.