The correct answer is B.
OBJ-2.4: Z-Wave is a wireless communications protocol used primarily for home automation. Z-Wave creates a mesh network topology, using low-energy radio waves to communicate from one appliance to another. Devices can be configured to work as repeaters to extend the network but there is a limit of four hops between a controller device and an endpoint. This allows for wireless control of residential appliances and other devices, such as lighting control, security systems, thermostats, windows, locks, swimming pools, and garage door openers. Zigbee is a low-power wireless communications open-source protocol used primarily for home automation. Zigbee uses radio frequencies in the 2.4 GHz band and a mesh topology. Near-field communication (NFC) is a set of communication protocols that enable two electronic devices, one of which is usually a portable device such as a smartphone, to establish communication by bringing them within 4 cm of each other. This is commonly used for contactless payment systems, transferring contacts, or transferring a file from one device to another. Bluetooth is a wireless technology standard used for exchanging data between fixed and mobile devices over short distances using UHF radio waves in the industrial, scientific, and medical radio bands from 2.402 GHz to 2.480 GHz and building a personal area network (PAN). Bluetooth is commonly used when connecting wireless devices like mice, trackpads, headphones, and other devices.