Harald Bluetooth was king of Denmark long ago. He united Denmark andpart of Norway into a single kingdom. Harald was killed in battle in986 when his own son whacked him with a sword. But his nickname liveson in an unlikely place. Bluetooth is the name of a method ofconnecting electronic devices without wires. Although Harald hadnothing to do with wireless technology, the choice of his namerecalls the important role played by the countries of northern Europein the modern communications industry.

Oneof the most common uses of Bluetooth is in mobile telephones. If aphone contains a Bluetooth chip (晶片),it can transmit and receive information to and from any other devicethat has a similar chip. Children and teenagers are increasinglyusing Bluetooth to exchange pictures, videos, and music. They justneed to be standing close enough to each other for the devices tocommunicate. Unfortunately, many kids are not aware they may bebreaking copyright law when they share music in this way.

Bluetoothis also useful for personal security. An amusement park in Denmark isusing the technology to help parents keep track of their children.Parents can rent a band to fasten around the child's wrist. If thechild disappears, they just have to send a text message asking forthe location of the band. In an instant, they can find out exactlywhere the missing child is.

44. The passage is mainly about _______.

(A) the function of Bluetooth in communications technology

(B) Bluetooth, the king of Denmark

(C) Bluetooth, the easier way to download videos and music

(D) how Bluetooth chips keep track of information