Amara wants to pay at a shop terminal by briefly tapping the back of her phone against the reader, with no cable and no menu to select a device. Which mobile technology enables this tap-to-pay pairing?
- ABluetooth, which pairs two devices wirelessly over several metres after a discovery step
- BNFC, which links two devices at a few centimetres for contactless tap payments Correct
- CInfrared, which sends line-of-sight signals between two closely aligned device windows
- DWi-Fi, which joins a device to a network access point across a room or building
Why A is wrong: Bluetooth is wireless and used for accessories, but it works over several metres and needs a pairing or discovery step, not the brief physical tap described.
Why B is correct: NFC operates at a range of a few centimetres and powers contactless tap-to-pay, matching Amara's brief phone-to-reader tap with no menu.
Why C is wrong: Infrared is short range, but it needs an unobstructed line of sight between aligned ports and is not used for contactless payment terminals.
Why D is wrong: Wi-Fi connects devices to a network over long range, which is tempting for wireless, but it is not the very short tap technology used at payment readers.