A user is looking for a wireless headphone for listening to songs stored on a smartphone. What wireless technology would the headphone use?

Bluetooth is a wireless technology for data exchange over a short distance. It is suitable for connecting devices with simple tasks, such as headsets, keyboards, mice, and printers. Wi-Fi is suitable for variety of applications with high speed wireless connectivity required or preferred. Infrared requires a direct line of sight between the transmitter and the receiver. 3G/4G are cellular network technologies to manage voice calls and data transmission between clients and service providers.