[Ans] Which of the following technologies derives its name from a 10th century viking king?

	Harald Gormsson was a king of Denmark and Norway. He was the son of King Gorm the Old and of Thyra Dannebod. His father had been the first ruler of the Danish kingdom and founder of the Jelling Dynasty.
	His full name is Harald "Bluetooth" Gormsson. The Bluetooth wireless specification design was named after the king in 1997.
	Other Interesting facts :
	In autumn 2014, the curmsun disc, a golden disc bearing the name of Harald Bluetooth, appeared in Sweden.
	Harald introduced Christianity to Denmark.
	Harald ruled as King of Denmark from c. 958
	As a consequence of Harald's army having lost to the Germans at the Danevirke in 974
	Harald was killed fighting off a rebellion led by his son Swein