Which of the following wireless technologies only requires one of the devices to be connected to a power source?

RFID (Radio-Frequency Identification) is a broader category that includes both passive tags (which can be unpowered) and active tags (which require their own power source). NFC is a specific type of high-frequency passive RFID, but RFID itself is not exclusively passive.

NFC (Near Field Communication) technology commonly uses passive tags that do not require an internal power source. These tags are powered by the electromagnetic field generated by an active NFC reader device, allowing them to communicate wirelessly with only the reader powered.

Bluetooth devices, such as headsets or controllers, typically require both communicating devices to be powered by their own batteries or external power sources to establish and maintain a connection.

Z-Wave devices, commonly used in smart home automation, are generally active components that require their own power source, either battery or wired, to operate within the mesh network.