The correct answer is C. RFID/NFC.
RFID (Radio Frequency Identification) and NFC (Near Field Communication) are two technologies that can be used to identify tags, devices, and smart phones. RFID uses radio waves to identify tags, while NFC uses near-field magnetic fields. Both technologies can be used to track and monitor objects, and they can also be used to provide access control.
RFID is a more mature technology than NFC, and it is used in a wider range of applications. RFID tags can be passive or active. Passive tags do not have their own power source, and they rely on the energy from the RFID reader to power the tag’s antenna. Active tags have their own power source, and they can transmit data to the RFID reader over longer distances.
NFC is a newer technology than RFID, but it is growing in popularity. NFC tags are typically used in mobile devices, such as smartphones and tablets. NFC can be used to make contactless payments, to share data between devices, and to access secure areas.
Both RFID and NFC are useful technologies for identification. RFID is a more mature technology, while NFC is a newer technology that is growing in popularity. The choice of which technology to use depends on the specific application.
A. IETF 6lowpan is a protocol that is used to enable IPv6 communication over low-power wireless networks. It is not a technology that is used for identification.
B. IEFT CoAP is a protocol that is used for constrained application protocols over the Internet. It is not a technology that is used for identification.
D. IEEE 802.15.4 is a standard for low-power, low-rate wireless personal area networks. It is not a technology that is used for identification.