Which of the following can be used to gather network information or user data?

• A. RFMON
• B. Packet sniffer
• C. Whaling device
• D. None of the above

Answer: (B)

Packet sniffers are tools that listen to network traffic and log the packets that traverse a network. By capturing these packets, they reveal who is talking to whom, what services are being used, and, if the traffic isn’t encrypted, the actual data being sent. This makes them the primary way to gather network information or user data. In wireless environments, monitor mode (RFMON) enables a wireless card to capture traffic from the air, but it’s a capability rather than a standalone data-gathering tool. A “whaling device” isn’t a recognized tool for this purpose, and “none of the above” isn’t correct because a packet sniffer exists. So the packet sniffer is the appropriate choice.