Which of the following Bluetooth hacking techniques does an attacker use to send messages to users without the recipient's consent, similar to email spamming?

Bluesmacking is a Bluetooth denial-of-service attack that sends oversized L2CAP echo request packets to crash or freeze a target device.

Bluesniffing refers to passively capturing and analyzing Bluetooth radio traffic to intercept communications.

Bluesnarfing is the unauthorized access and theft of data such as contacts, calendars, and messages from a Bluetooth device without the owner's knowledge.

Bluejacking exploits the Bluetooth object push profile (OPP) or the device name field to transmit unsolicited contact cards or messages to discoverable devices within range. It does not grant the attacker access to the victim's data - it is purely a nuisance or social engineering vector. The analogy to email spamming is direct: messages are pushed to recipients who did not request them.