I believe the answer is A
The answer to that would be that
they require so its mandatory for mechanical waves to travel through a medium
Answer:Near-field communication
Explanation:
Near Field Communication is an umbrella term that applies to location-aware technologies that allow devices to communicate securely with each other over short distances. Near-field communication is a short-range wirelessconnectivity standard that uses magnetic field induction to enable communication between devices when they're touched together, or brought within a few centimeters to each other.It also specifies a way for the devices to establish a peer-to-peer network to exchange data. After the peer to peer network has been configured, another wireless communication technology, such as Bluetooth or Wi-Fi, can be used for longer-range communication or for transferring larger amounts of data.
